help name this romantic movie about a girl with a metabolic condition

Hi. All I remember about this movie is that a terminally ill girl who needs large intakes of food frequently, bumps into this bachelor, a young man who is in the habit of stealing to the rooftop at his workplace to smoke while he's chatting to his mate. The girl moves in with the guy, but leaves him unannounced when she needs to check into a hospital for treatment. I'm afraid I never got to watch the ending, so I'm not sure what more happened between the two of them or how they ended up.
Thank you, guys!

That film doesn't sound familiar to me. Has anybody here seen Thief of Hearts? It's about a woman who has a break in at home, amongst the items stolen is her diary which the thief reads, i think the woman is called Mickey, and she starts to fall for the thief. Great film but i never got to see the ending!😢