My life is weird!

Okay, story time:
I met this one guy through some mutual friends, and he's in a really bad marriage where he's not happy and neither is his wife. They got married young and it isn't working out. Anyway...we started hooking up, just a sex thing. One of the biggest problems in their marriage is that they don't like having sex with each other. The sex I have with him is GREAT, I've never been this compatible with someone before.
Anyway, it just started as sex, but now we're friends and I have really strong feelings for him. He's always asking me for relationship advice to fix his marriage, but at this point...all I want is for him to get divorced. 
I feel so weird about this whole thing! I think the two of us would make a great couple, but even if we didn't date after the divorce I really think it's the best option for them.
Anyone been in a similar situation? Thoughts? Advice? I feel so lost...