This is so good and so painful. You've really captured their characters perfectly, how Tim's pain has made him kind of vicious and uncaring. And how Martin is so willing to sacrifice anything, do anything, for someone else, without caring about himself or how it hurts him. All that matters is helping Tim. And you really weave that in so well, all the points Martin should have said no, when he wasn't comfortable at all. Hell, going for it in the first place. It's heartbreaking and beautifully done.