I have had the same issue over the past year and a half. He claimed to have forgiven me after a lot of back and forth on his part. My lie was concerning texts sent to another friend of mine. He confronted me about them because he believed i was flirting and making suggestive remarks. I, on the other hand, was truly not doing anything like that purposefully. I was commenting/bantering in the heat of the moment and he saw it as something else. Because I didn't fully explain the conversation, he looked through my phone and things got worse and worse. I changed my phone number and promised myself and him that I would always be honest and open even if I think the subject doesn't matter. I've never been one to be very open, so on the plus side, this helped me grow as a person.
Over the next year and a half, he has struggled with fully trusting me. It isn't an easy process and may never be fixed. I used to believe that time, communication, and faith would heal him, but that hasn't been the case. He still gets unexplainable sinking feelings every once in a while and it is tearing us both apart. From what he says, nothing triggers it. I think the trigger is poor communication and lack of closeness, but I can never know. He won't even listen to what I have to say. As of yesterday, he wants nothing to do with me even as a friendship. I feel that will only create more distance and increase his suspicions considering we do still see each other, have many mutual acquaintances, and work at the same place. We can get along but the intimate relationship we had before is basically non-existant since he can't bring himself to fully trust again. It is definitely painful.

I don't know if this will help you, but they seem to be similar cases. I just wanted to point out that it could take a very long time and will likely result in a lot of heartache, sadness, and sick feelings. I hope that your situation improves. I know the situation probably feels like it is consuming most of your life. I hope that this forum can help you. Have faith and be patient. That's all you can really do. He will have to choose to forgive and trust on his own.