Tunick's mysterious ailment has forced her to refocus her priorities. When ABC News correspondent Bob Brown asked Tunick what her dream is, her answer was realistic and short term: "I need to get somewhere."
Mendenhall agrees. "All my attention and focus and -- goals right now are ... getting her somewhere."
Yet, just "getting somewhere" is not as easy as it sounds, and even a simple trip to the local doctor calls for painstaking preparation.
"We have to use my father's car. We pad the back of it ... for me to lay in the back. And it's very painful. And I get really stiff with the bumpiness and the padding," Tunick told ABC.
Through it all, the couple tries to focus on each other and the positive aspects of their lives.
"I can't be depressed and down and negative, 'cause I know that's not gonna help her," Mendenhall said. "Even though it's hard."
Their relationship has significantly transformed with Tunick's decreasing health, but their dedication to each other remains. Because of Tunick's limitations, they spend most of their time together in bed.
"Just sitting next to each other is romantic. And being with each other, and just seeing him and smiling -- that's romance," Tunick said. "You don't need gifts and flowers ... you just need that mental connection."
Tunick keeps her yearly resolutions posted on the wall next to their bed, a daily reminder of her hopes and aspirations for the near future: "Get healthy enough to leave the condo. Get in shape. Eat healthy. Stay positive. Keep hope. Stay organized."
And lastly, and most importantly, "And always keep Brian as my first priority."
For Tunick, her medical future remains uncertain. Their love for each other, however, remains a comforting constant.
"I made a choice to stick by her side. And I am. And I will ... 'til the end," he said.
He said he wants Tunick to know "my life's fine. My life is great with you. My life is nothing without you. Remember that."
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