I did something horrible.

So me and my boyfriend has been together for almost a year. We’re a pretty unproblematic couple aside from a few normal small arguments here and there. Except for when he went out of towns were gonna call him t. T went out of town and while he was gone we argued continuously like almost non stop for two weeks and when he came back he was super distant for about two more weeks. Barely talked to me barely wanted to talk otp we literally talked for 2 hrs throughout the day but he would go hang out with his friends everyday and he said he didn’t see a problem with it. That went on for 2 weeks after he got back. I thought our relationship was over honestly I thought he was done with me. Anyway I decided to reach out to an old friend well call him D. D had been the guy that I’ve gone too when my boyfriends fall short. Honestly our relationship has always been I talk to d until until I get into a relationship then I stop until that relationship is over. Now me and T are getting better and I actually think we’re gonna make it and be ok but D recently told me that he thought we were in an on and off relationship. I never even new that he liked me emotionally. I thought he only like me sexually (we never had sex just mostly talked about it) but ig I was wrong... so I felt bad for breaking him off every time I got into a relationship so I decided to just try and be friends. I now realizing that I never really explained that to him but he still sometimes makes inappropriate comments and I just tell him that I’m still In a relationship and he stays respectful. Anyway I feel guilty. I feel guilty for shortchanging me and Ts relationship and I feel bad for jurking D around. I know that the friend thing with D isn’t going to work and I have to break it off with him again because I feel too guilty like I’m cheating on T. What do I do. Ik I’m a horrible person.