This week, that momentous news out of washington and the supreme court, the overturn of doma, allowing gay couples to marry, recognizing thei love for one another. Tonight here, we start with a... See More
This week, that momentous news out of washington and the supreme court, the overturn of doma, allowing gay couples to marry, recognizing thei love for one another. Tonight here, we start with a different kind of love story. Two teenagers who completely changed their identities, shunned, targeted and alone. Until they met each other. And once you meet them, you will never forget them. And you won't forget their mothers, either, who played match maker, supporting their children every step of the way on their long and often painful journey of transformation. Here's deborah roberts with what every high school has -- the class couple. Reporter: It's friday night in tulsa, oklahoma. 18-year-old katie and 17-year-old boyfriend arin are getting ready for a night out on the town. The young sweethearts have been dating for more than a year and clearly remember the first moment they met. She walked in and I was like, "who's that girl?" He was just so handsome. I couldn't keep my eyes off of him. He would look out and see me, and I'd look away we'd be on the dance floor, I'd be dancing, I'd turn around and he'd be there. Reporter: Instant attraction? Oh, yeah. Instant, yeah. Reporter: Katie and arin are like any other teenage couple in love, except, and it's a big except, they were each born the opposite sex. That's right, arin was born a girl. Katie, a boy. They're transgender. Last year, katie had her body transformed with gender reassignment surgery. For now, arin is simply taking male hormones. When you undress, thh, you still have female genitalia. From face up, I look male. And when I get my clothes off at home at night, ie still got breasts and the female, biological genitalia. He walks like a man, talks like a man. He is a man! Even if he has breasts, or has a vagina. It doesn't matter. Reporter: And it is so ironic, because the parts that you want, you had and now you -- she got rid of them. Oh, yeah. It would just be perfect if we just switched because, you know -- you can have my uterus! You can have it all. He had the perfect breast size that I wanted. I said, well, you can have my penis! That would be great! Reporter: Oddly enough, it was katie's mom, jazzlyn, who brought them together, after seeing arin at a local transgender teen support group. We've got to get you two together. And I said, you know, you'd be perfect for each other. And I thought, who in the world would understand more of what she's feeling, and what she's gone through than a boy that's going through the same thing she's going through? Reporter: Katie, born luke, had struggled with gender identity ever since she was a toddler. I had male genitalia, but everything else was feminine. The waist, the butt, the cheekbones, the hair, the everything, the voice. It was really confusing for me, growing up. Reporter: At what point did you feel like you weren't meant to be luke? 3 or 4. I remember when I was 4, running into my mom's bedroom and pulling on my, you know, penis, saying, I want this off, mom. Off, off. Reporter: What did you think of that as a mom? You had to think that was pretty strange? Here was so much other stuff. When kale tee was luke, she was such an extreme, feminine little boy. Everything he did he swayed through it. It was very, you know, ballerina type. I just started goi, okay. I need to start preparing for the fact that, we have a gay son. Whenever I would go to sleep, I would dream myself wearing a white wedding dress, with long flowing hair, the perfect image of me as a woman. Reporter: Just 15 miles away, arin was the perfect image of a little girl. Her mom named her emerald and was over the moon. When I had her, I was like, "yes! I got a girl." I wanted a girl so bad. She was like, the best thing that's every happened. Reporter: Denise put emerald in dance and pageants. She was so proud of her daughter's accomplishments, never realizing how uncomfortable emerald was in such a feminine world. I just felt out of my place. Ke, I wasn't supposed to have this dress on, I was actually supposed to have pants on. I identified with the guys. I THOUGHT I WAS A GUY. Reporter: Growing up, luke and emerald both felt like outcasts. Soyou had to endure a lot at school. I was bullied there for, like, ten years. Reporter: Because you were an awkward girl? Because I was different. I talked like a man, I walked like a man, but I wore a skirt. Reporter: He was depressed and isolated. Just like katie. She spent her whole childhood in the corner of her room, with the door closed and the lights out. Everyone hates you, and you hate yourself. You know, there's no one on your side, not even you. My firttempt at suicide, i was 7. One time, I tried to drown myself in our pool, with cinder blocks. Reporter: A staggering 41% of transgenders will attempt suicide. It was jazzlyn's worst fear. I think it was just the matter of days. Reporter: And you hear your kid in the other room -- I literally just started yelling at him. I know what you're getting ready to do and I'm not going to a it. I said, just tell mel you're gay. We'll get through it, we'll figure it out. It's not that big of a deal. He finally just yelled at me that he was transgender and i just kind of stopped. Reporter: Did you have any idea what transgender was at that point? I guess I thought that transgender was transvestite. And I'm just thinking, okay, so, you want to wear girls clothes. I got a whole closet in there. Go! If it will make you happy and it will keep you alive and it will make you laugh, you know? I've never seen you laugh, in eight years. She asked, will this make you happy? Will this make it so I don't have to be afraid of coming home every day, and be afraid of seeing you dead on the floor? And I said, yes, this is going to help, mom. This is it. This is what I need. And I said, you know what? Just tell me what you want. I will do anything that you want me to. The very first thing out of his mouth was, he says, I want bras and panties. I said, fine. We'll go to victoria's secret tomorrow. I wanted to change my name, i wanted to get on hormones -- i wanted to grow my hair out, be called she and her and katie, not lucas. And and I don't care if it takes every ounce of being in my body. I will not stop until everything on that list is done. And damn, she did it. She sat my family down and said, lucas is now katie. He is she. If you have a problem with it, there's the door. Reporter: The defining moment for arin came at age 14, struggling to live life as a girl. He was kicked out of a private christian school. I was asked to leave, because I put on too many suspicions that I was a lesbian. I went home that night. I curled up in a ball and cried. I had a knife and I tried to slit my wrists. Reporter: In the depths of despair, arin searched the internet for answers, and realized he wasn't gay, he was transgender. It's like being sick for years and not knowing what you have, and that moment when you figure out what you are, you can help yourself. You know, it's like one of those great moments. Reporter: He broke the news to his mother, denise. What is it like, as a mom, hearing your only daughter say that you don't really have a daughter? Well, it's hard, I mean -- i was losing my little baby girl. When you have friends that have had daughters with you, and they're going to the prom, and picking out dressing and -- I'm going to miss all that. She had to mourn the loss of her daughter. I mean, no parent wants to go through that. Is the right needle on there? Reporter: Now, instead of helping emerald prepare for dance recitals, she helps arin with his testosterone shots. An unusual perk of the relationship -- the teen lovebirds can swap clothes! This is pretty pink -- jaw-droppingly gorgeous like the first time I met you. Reporter: Katie has her pick of arin's old dresses. I had to wear that dress three times. If you would have told me a year ago that I'd be in the place that I am now, I would have been like, good joke. I would have laughed in your face. You know, it's funny, where, where I've been, and where I'm going. Because I would have never known that thud would have happened to me. They were robbed of their childhood. Marshmallows. Yeah. They're just trying to catch up on life, and they're living it and they're loving it. Since then, deborah tells us that arin has undergone even more of a transformation. Undergoing surgery to remove his breasts. What a story
This transcript has been automatically generated and may not be 100% accurate.