Help on dating a separated man!

Ok! So I've been dating this guy for a few months now. He's still legally married but has been separated for a year. I've never dated a man in this situation before and I'm not really sure how to handle it.

Basically his wife cheated on him multiple times throughout the marriage and he finally had enough and left her. But it's their wedding anniversary tomorrow and I know he's a bit down and upset.

We were supposed to be seeing each other this weekend but he's now told me he's got to work and can't see me. I might just be being paranoid but I can't shake the feeling that he's lying to me! I honestly think he just doesn't want to see me this weekend because it's his anniversary.

I have no concerns that he might be seeing his wife or anything like that. I think I'm just finding it hard to understand why he's so upset about it all when his wife literally treated him like shit for years during their marriage!

He constantly compares me to her but in a way like 'oh I like that you do that as Jane never wanted to do anything like that'

It really annoys me that he does that.

To be fair I think I'm just looking for a bit of advice from anyone whose ever dated a guy that's separated! Is this relationship doomed before it's even really begun!!

Just need a little bit of help/advice or if anyone can tell me what they've been through in a similar situation. I'm really falling for him I just don't want to be a fool and get hurt!!