Opinions wanted

I've been seeing this guy a couple of months now, when it started it started as a "no strings" as he was still with his ex. They were living opposite ends of the country and hadn't seen each other in a long time. Nothing serious happened between us while they were still together.
He kept telling me they weren't happy together and making comments like "I would date you" and with no more than two weeks overlap he broke up with her. When I asked him about it he said I was the only time he'd been unfaithful to her and that he wanted a reason to leave.
I asked where we stood and he said he didn't know. He didn't want a relationship but let's just see where it goes.
Now he is constantly going on about wanting to come on holiday with me in years time and is behaving as though we're in a relationship. Going out for food, staying round at mine, cuddles kisses hand holding.
He's also had several family tragedies while we've been seeing each other (his cousins was murdered and then his nephew died of cot death) he has called me for emotional support both times. As soon as he found out.
So my question is should I trust him? What does he want? Am I being used as an emotional crutch? Should I let myself catch feelings or keep it casual?
It's getting real confusing up on this side!