Trust is the bases for all relationships without trust there is no relationship. You might as well get out if you really want out. If you and he have not built up trust by now it just isn't going to come someone has some "trust" issues that need to be resolved.
I can see why you are pulling away it is a terrible feeling to know someone doesn't trust you. You feel guilty and you haven't even done anything.
Breaking up, well there is no nice way to break up with someone if you figure out how not to hurt them well you would be a millionnaire. Someone always gets hurt it is just the nature of the beast.
What you do is keep your respect and be honest without saying anything to hurt the person and don't go into detail when he asks "why" you will find yourself in a loop you can not get out of. You have to keep is simple and straight forward. Don't look for the person to be "all right" about it no matter how gentle you are they are going to be angry once it sinks in that you really are breaking up. But it is better than staying and faking it. You will end up doing him more harm and if he knew you were doing that wouldn't he feel awful like he was being humored because you were staying with him for all the wrong reasons. No I would rather someone tell me they don't love me anymore than make me feel like a fool going on with the relationship and thinking we have something and find out we don't and haven't for a while. I would really get angry with you then.
Just tell him in private realize he isn't going to understand and he is going to want explanations and he is going to try and make you stay and he is going to try and make you feel guilty. Those are all givens. Now you have to stay strong and realize there is life after Brutus sorry but none of us is irreplaceable. Time thank God for time all things become clear with time and we all heal with time. You will be forgotten as far as the pain, he will meet someone else and hopefully say that he is glad in the end you broke up. But it takes time. SO stay away from him and let him heal. Don't do this "lets be friends." No one can be only friends with someone they are in love with and especially after being jilted. So forget that for soothing your conscience. Just be mature and take it knowing that in the end you are doing what is best for both of you so you can both move on and meet people that will be more to what you are searching for in a love relationship.
Well, let us know and I hope this helps,
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