You have my sympathies. My relationship of a year ended just a few months back and like you i'm finding it hard to move on. Both me and my ex made mistakes, it was my first serious relationship with a lady, and forgiving yourself for the mistakes that you made which came to overshadow the good times is an endeavor thats emotionally challenging at times. Those good times are hard to say goodbye forever to, i know. Despite being a guy i occasionally still find myself crying over them.
I'm in agreement both with Wren and Jumbelly.
I've come to see that perhaps i've been idealising the relationship since it ended: there were times i was unhappy with the relationship and questioned whether she was the girl for me due to behaviour she exhibited, yet its not those times i automatically remember nowadays. When we lose something we can have a habit of getting nostalgic over it, of looking back at it with selective memory. I find it helps to remind myself of the problems we had, the times i was unhappy or left hurt, etc. That way i've begun to see that in fact this relationship was not as fated to be as i'd come to convince myself. Thats another thing love can do to us - we see what we WANT to see in the other person, we let our hopes blind us to the reality.
Also, in my case this was my first serious attempt at a relationship... i made mistakes. At first i found them hard to face. There were aspects of myself that i was unaware of but now i can see. As Jumbelly says, its important to stop beating yourself up with guilt and forgive yourself.
Thats what i've started doing. At first i denied them, then i felt massive guilt over them. But living in self-imposed guilt won't help you grow and learn so that you can be even better in your next relationship. And thats what i'm starting to do... honestly analysing things about myself that i could improve, looking back on times where my standards fell short to see how i can eliminate such behaviour. Another thing i do is put my own failures into perspective... i didn't swear at me ex, shout at my ex, strike my ex or cheat on her... so, its not as bad as it could have been. There are good prospects for self-improvement!
Frankly, living in guilt is also pretty pointless... the relationship is over. Its not coming back.
I also agree with Jumbelly that if you were cheating then it couldn't have been as perfect as you have come to believe. I never cheated, but there were moments i came seriously close to leaving my ex because of things she did to me. Again, as i say after a breakup you can lose focus of these things and torture yourself by ruminating merely on the good times whilst losing focus of the bigger picture.
Wren's observation is also something that i share... marrying just 2 months later would make me pretty suspicious actually, and make me wonder just how deep her feelings were for me if she could get over them so quickly.
Like you, i also found that my ex wouldn't actually talk to me properly. I begged her for a time after we broke up to speak to me amicably about things so that i could get some emotional closure. She promised she would yet she never got round to it. However, to be fair to her i was an emotional mess and all over the place at the time so maybe i was too much for her to want to deal with. That lack of closure i sought from her made it hard for me to move on too. Like you i also asked her to forgive me for my mistakes... again, what feedback i did get was at best mixed on that score. As for her requesting that i forgive her for the things she did, thats never going to happen - she's not the sort of person to feel guilt or blame herself for anything. Not for long, anyway. I know she'll very quickly move on from me. My family assure me that the only person still moping over this is me. Perhaps my feelings for her were stronger than hers were for me. If so, that means i can take heart from the fact i'm a sincere, loving person. The depth and sincerity of your own guilt and emotional pain show that you're a sincere loving person too, fallentofar.
We are human. We make mistakes. We fall short. What makes is good people is not that we never make mistakes or let people down - its that we accept our mistakes, admit to them honestly, and work on ourselves so that we don't continue to repeat them over again.
Thats what i think, anyway. Its too easy to just leave a relationship and heap all the blame for everything on your ex. Too many people do that and learn nothing. The fact you are not doing that shows how mature you are.
One day, you will find yourself moving on and sharing happy times again with someone special that endures in your life. And because it endures you'll treasure the memory of them even more. Take all the time you need to heal.
All the best,