might break up again?

I dated my ex for 3 years (H) First love and my closest friend. We have remained friends on and off after the breakup, but we are always there for each other. I started dating my current boyfriend (K) a few months after, and have now been dating for 7 months.

We (K) met at school, and live in different states. When I came back to school I felt overwhelmed. With moving in, family drama, and the recent loss of some friendships, I couldn't handle even the slightest things he did that annoyed me.

I asked H for advice, and since he was in a similar situation, we were able to talk it out to each other.

I broke up w/ K after a week of being back at school, saying I needed to focus on bettering myself etc, which is true, but mostly I just didn't want to be with him anymore. He was shocked but very understanding.

Started hanging out H, since we were both having a hard time. We became intimate which confused me because I felt guilty for breaking up with K, being there weren't any problems with the relationship on the surface, I just wasn't into it anymore.

K's just not someone I can see myself ending up with, but we got back together. I think it was a mixture of guilt and my need for stability.

Before we got back together, I asked H if he wanted to get back together, because I still and will always love him. He said he couldn't commit then, and after I told him I got back with K, he admitted he loves me and wants to be with me forever.

I feel so guilty, but I do love H. I am currently dating K, and I know its not fair to me or him if I am not fully in the relationship because of feelings for someone else, but i just can't break up with him again. he would be heartbroken. I also have been depressed lately because of this whole situation and just life... and he has been such a great boyfriend always supporting me and helping me. I feel like I am just using him, especially if i were to break up with him.

My heart is telling me to go back to my first boyfriend, but my mind is telling me I am immoral for doing so.