'MarineSniper' and 'Talhotblond's' IMs

46-year-old, posing as Iraq-bound marine, meets 18-year old girl in chat room.

March 19, 2010— -- A chance encounter in an online chat room led to a romance between a beautiful 18-year-old girl named "Jessi" and a handsome young Marine. But what she didn't know was that her "sweet sexy Marine" was actually a balding, 46-year old married man, Thomas Montgomery.

What Montgomery didn't know was that the beautiful temptress was actually a 45-year-old home-maker Mary Shieler, posing as her daughter "Jessi" without her knowledge.

Click here for more on their cyber romance

Unaware that they're both not who they say they are, "Talhotblond" and "MarineSniper" flirted in an online chat room for nearly two years, exchanging photos, gifts, phone calls and love letters. Their flirtation escalated into an intense virtual relationship, which Montgomery told "20/20" felt "more real to me than real life."

Click here for love letters sent between "Jessi" and "Tommy"

But when Jessi learned who her online love really was, she broke it off with Montgomery and took up with his young hunky co-worker, Brian Barrett. It was only a matter of time until the "MarineSniper" enacted the ultimate revenge.

On Sept. 15, 2006, Barrett was found dead in the parking lot where he worked, shot three times by a military rifle. News among co-workers spread of the love triangle and when police couldn't find Montgomery, they feared he was heading to "Talhotblond's" house in West Virginia.

Montgomery was sentenced to 20 years in jail in a plea deal for Barrett's murder.

An excerpt of one of "Talhotblond" and "MarineSniper's" intimate IM conversations is below.

'MarineSniper' and 'Talhotblond'

MarineSniper1000 (6:26:40 PM):on friday or sat u can say goodbye forever to me and tommy

TalHotBlondbig50 (6:26:53 PM): why

MarineSniper1000 (6:27:03 PM): we r leaving for good

TalHotBlondbig50 (6:27:07 PM): no

MarineSniper1000 (6:27:29 PM): yes jessi u r having fun in ur life now so its time for us to leave

TalHotBlondbig50 (6:27:42 PM): no tom

TalHotBlondbig50 (6:27:51 PM): dont take tommy

MarineSniper1000 (6:28:09 PM): hes going with me u replaced him with timmy

TalHotBlondbig50 (6:28:29 PM): please dont say that

TalHotBlondbig50 (6:28:32 PM): its not true

MarineSniper1000 (6:28:50 PM): according to the text i got it is true

TalHotBlondbig50 (6:29:01 PM): no it isnt

MarineSniper1000 (6:29:31 PM): so its time for tommy to be put to rest

TalHotBlondbig50 (6:29:52 PM): i will leave

MarineSniper1000 (6:29:56 PM): i wish i had a perfect life like u and brian do

MarineSniper1000 (6:30:10 PM): that is up to u jessi its ur choice

TalHotBlondbig50 (6:30:15 PM): what does brian have to do with this

TalHotBlondbig50 (6:30:34 PM): ur not going to forgive this one

MarineSniper1000 (6:30:36 PM): he left a few copies of ur conversation on my tool box today

MarineSniper1000 (6:30:52 PM): half the company knows now

TalHotBlondbig50 (6:31:00 PM): knows what

MarineSniper1000 (6:31:09 PM): what u 2 talked about

TalHotBlondbig50 (6:31:14 PM): no tom

MarineSniper1000 (6:31:25 PM): how u told him im a ******* loser and predator

MarineSniper1000 (6:31:38 PM): i dont have a life

MarineSniper1000 (6:31:57 PM): 3 hours u 2 were talking about me

TalHotBlondbig50 (6:32:01 PM): what did u say to him

MarineSniper1000 (6:32:07 PM): i didnt

TalHotBlondbig50 (6:32:12 PM): why not

MarineSniper1000 (6:32:22 PM): its not worth it anymore

TalHotBlondbig50 (6:32:58 PM): i will get out of ur life tom ..... i have done to much damage to be undone now.... im so sorry

MarineSniper1000 (6:33:07 PM): u made it perfectly clear who u want by ur talk with brian

TalHotBlondbig50 (6:33:14 PM): u will never forgive me

MarineSniper1000 (6:33:17 PM): that is up to u jessi

MarineSniper1000 (6:33:25 PM): i will on sat

TalHotBlondbig50 (6:33:27 PM): what do u want tom

TalHotBlondbig50 (6:33:36 PM): u will what on sat

MarineSniper1000 (6:33:45 PM): forgive u

TalHotBlondbig50 (6:33:52 PM): why saturday

MarineSniper1000 (6:33:59 PM): im leaving

TalHotBlondbig50 (6:34:07 PM): where r u going

MarineSniper1000 (6:34:14 PM): to hell i hope

TalHotBlondbig50 (6:34:19 PM): tom stop

TalHotBlondbig50 (6:34:27 PM): why r u saying that

MarineSniper1000 (6:34:28 PM): my heart will exist no more after sat

MarineSniper1000 (6:35:03 PM): so i will forgive u with a email then the tom and tommy u knew will no longer exist

TalHotBlondbig50 (6:35:21 PM): no tom u cant do that

MarineSniper1000 (6:35:30 PM): yes i can and i will

TalHotBlondbig50 (6:35:34 PM): why

MarineSniper1000 (6:35:37 PM): i will be alone

MarineSniper1000 (6:35:55 PM): and will never feel compassion for another person til i die

MarineSniper1000 (6:36:28 PM): u could have been honest with me jessi instead of crying on brians shoulder

TalHotBlondbig50 (6:36:42 PM): i know

TalHotBlondbig50 (6:36:47 PM): im sorry tom

MarineSniper1000 (6:36:56 PM): its too late jessi

MarineSniper1000 (6:37:10 PM): this ******* loser is leaving on sat

TalHotBlondbig50 (6:37:24 PM): please dont do that

MarineSniper1000 (6:37:32 PM): y do u care

TalHotBlondbig50 (6:37:41 PM): u know i care and why

MarineSniper1000 (6:38:06 PM): after what i read u dont give a shit about me or ur tommy

TalHotBlondbig50 (6:38:22 PM): ur wrong

MarineSniper1000 (6:38:26 PM): do u want me to repeat what u said or do u remember

TalHotBlondbig50 (6:38:36 PM): no i remember

MarineSniper1000 (6:38:50 PM): u still have it dont u

TalHotBlondbig50 (6:38:55 PM): no

MarineSniper1000 (6:39:31 PM): then u begged brian to stay with u when he told u to leave him alone

TalHotBlondbig50 (6:40:21 PM): life was so much better when u were my tommy

MarineSniper1000 (6:40:38 PM): y couldnt u tell me u wanted to be with brian

TalHotBlondbig50 (6:40:47 PM): i dont want to be with brian

MarineSniper1000 (6:40:50 PM): tommy is leaving u on saturday

TalHotBlondbig50 (6:40:57 PM): i dont want to be with anyone but tommy

MarineSniper1000 (6:41:10 PM): sure sounded like it with what u wrote to him

TalHotBlondbig50 (6:41:26 PM): tom please stop

MarineSniper1000 (6:41:39 PM): y does the truth hurt jessi

TalHotBlondbig50 (6:41:58 PM): no the truth doesnt hurt but u r hurting me

TalHotBlondbig50 (6:42:05 PM): the truth i can handle

MarineSniper1000 (6:42:31 PM): then tell me y u say u dont want to be with brian to me but u tell him u want to be with him

TalHotBlondbig50 (6:43:15 PM): i dont have that answer

MarineSniper1000 (6:43:25 PM): then it is true

TalHotBlondbig50 (6:43:29 PM): no it is not

MarineSniper1000 (6:43:49 PM): y did u beg him to stay with u then

TalHotBlondbig50 (6:44:05 PM): i didnt

MarineSniper1000 (6:44:22 PM): according to what u wrote please dont leave brian

TalHotBlondbig50 (6:44:36 PM): i didnt write that

MarineSniper1000 (6:44:49 PM): it has ur name on it

TalHotBlondbig50 (6:44:54 PM): show me

MarineSniper1000 (6:45:00 PM): jessi xxxxxxxxxxx

MarineSniper1000 (6:45:09 PM): isnt that ur name on yahoo

TalHotBlondbig50 (6:45:24 PM): yes

TalHotBlondbig50 (6:45:28 PM): show me

MarineSniper1000 (6:45:30 PM): ok

MarineSniper1000 (6:45:39 PM): u ask brian to send it

TalHotBlondbig50 (6:45:50 PM): i dont talk to him anymore

MarineSniper1000 (6:45:53 PM): i am mailing all of it to u on saturday

TalHotBlondbig50 (6:45:56 PM): im asking u

MarineSniper1000 (6:46:06 PM): u will get it sat

TalHotBlondbig50 (6:46:17 PM): why not now

MarineSniper1000 (6:46:32 PM): im not done reading what u 2 talked about

MarineSniper1000 (6:46:54 PM): good thing u 2 have a perfect life so u can talk about me

MarineSniper1000 (6:47:10 PM): 3 hours jessi u cried to him

MarineSniper1000 (6:47:22 PM): and that is only one night

MarineSniper1000 (6:47:52 PM): then u have the gall to tell me u love me and want me to stay in ur life

TalHotBlondbig50 (6:48:13 PM): ok tom

MarineSniper1000 (6:48:19 PM): tommy and i have been replaced