How do you recover from distrust?

[StarCrazy]

Wasn’t sure where to post this (Feel free to move).

Storytime:
I have a friend (call him X) who I’ve known for 17 year roughly. He was very supportive of me when I had my breakdown and ever since then. Always encouraging me to come out, share music, etc. As was his girlfriend (we’ll call Y) who I’ve been very close friends with and also known for a similar time period.
A year ago X cheated on his Y. They’d had multiple breaks before but never due to cheating. Y was really upset and distraught for months. They had been talking about moving away together and it obviously came out of no where. X cheated with someone he had just met while he was on holiday (in another country) and it seemed kind of something that he obviously initiated.

All my friends with him and made it known they were upset with him and that it wasnt okay. And he kind of understood he made a bad choice. I kind of told him I thought it was really dumb and that if he wasn’t happy he should have just said and it wouldn’t have been a big deal.
But overall I also tried to be supportive as I knew he didn’t have many people trying to help him.
But he would tell me about his new girl friend (Z) and it would really upset me, but I tried to just keep it to myself. I thought how long can a relationship in two different countries actually last? And expected it to fizzle out. I also thought eventually I’d get used to it, and it was the period of change I was struggling with.

Well fast-forward a year, and X and Z now live together in the same country and have been together. At the same time, I’ve been hanging out with Y a lot more than X (as have all our friends).

Actual problem:
The problem I have is that while I want to be friends with X still, I physically/emotionally don’t feel like I can be. I quit our band because I just feel really uncomfortable with him. I was sometimes having intrusive thoughts about making a scene in our band sessions. Imagining answering questions bitterly to take him down a peg.
Even with more people and less focused environment I still, feel really resistant and kind of nervous around him. Even when I’m not having intrusive thoughts I just feel distrustful.
I’d like to move past it, but I don’t know how. Again its not that I dislike him, I just physically don’t feel trusting of him.
Does anyone have advice?

[Truemist8]

My x boyfriend will not take me back because he doesn’t trust me.

He doesn’t trust me because I left him with out telling him I was until a week before I did.

He lets me be his friend and fan and buy him stuff but he is short with me.

He doesn’t make conversation.
He may say hi and nothing else.

You can love people you don’t trust.

I avoid people I feel uncomfortable around.

So if I was you and felt uncomfortable around him I would avoid him.

I feel uncomfortable around my sister.
Because she is my sister I love her and see her at family get togethers and once in a blue moon for a walk but otherwise I avoid her.

Why hang out with someone who makes you feel uncomfortable?

That will make you suffer being with them.

Be with those you feel comfortable with.

[LilyoftheValley]

Let go of any bitterness towards x, but hang on to wisdom learned from X’s mistakes. In other words, stop holding a grudge and anger, but be wise in remembering what x did that makes you not trust him so that you don’t get hurt in the future. Over time, you may learn to trust x again.

[Illvoices]

I’ve been asking myself the same question I mean I’ve done nothing to loose the voices trust. Yet they come at me like they were going to attack or even kill me and that part of the voices is scary.