Trouble in relationship.

I’ve never posted one of these because I don’t like to put my business out in the world. But I don’t really have anyone to talk to about this. So here it goes. Today my bf of 2 years, found some messages I sent my ex about 3 months ago. I sent him a pic of me and was just looking for attention really... anyways, I was out of town when I was messaging him.

So my bf found them today and at the beginning of our relationship, he saw some messages from the same ex and we had a talk about it and so now we are here again.

Idk why I kept talking to him. He is now and has been blocked from my socials for a while now and I deleted his phone number.

But now my bf really don’t trust me. Not even a little. I just don’t know how to make him trust me again. Obviously I’m not mad about the situation I’m just disappointed because I knew it was a mistake and I made it. And I regret it. I just don’t know how to make him see that I truly love him and I regret everything....