Dealing with loss in subsequent relationship

I’m hoping someone can help me out with this.

I’m married and pregnant and my husband is such an amazing guy. We’ve known each other since 14 and dated on and off since 15 (I’m now 28 and he 29.) I can go into detail about all the things he does for me or the ways we are perfect for one another and how much I love him, but I’ll try to make this as short as possible.

My issue is that when we were broken up after college for a bit I started dating someone else. It was intense. Besides being the most attractive guy I’d ever met in real life I looked up to him. We had amazing chemistry and Just worked together so well as a couple. We hadn’t been dating very long when he passed away

I was absolutely devastated and it took a while to get over it. There were a lot of things left unresolved and I never got closure, but ended up back with my ex (now my husband.)

Most of the time everything is perfect in our relationship, but whenever we argue about anything or he does something to upset me I can’t help thinking the guy I was with before wouldn’t have ever said/done that and comparing, and wondering.

Maybe the two of us wouldn’t have worked out. We were still in that first year honeymoon phase of our relationship when he died, and it’s not like we never fought or had a perfect relationship either, but with something like this you tend to look back on all the good and forgot the bad.

There is just this big what if. Because the truth is we didn’t break up, so he’s technically not my ex in that sense of the word. In that short time I loved him and can’t help thinking what would be different if he was still here.

I never tell my husband this of course because I don’t want him to feel badly. It’s unfair to compare him with someone who’s not around anymore, but I feel such guilt because I can’t help doing or thinking it, even though I’m happy and wouldn’t change my husband or circumstances at all, and then if I don’t think of the man who I lost I feel guilty about that too because to forget about him feels heartless.

Is there anyone else who had a partner die and then dealt with guilt and the loss in your next relationship?