I cheat on my bf and won't stop

I'm (f22) cheating on my bf (m21) with my coworker. So I'm bf's first relationship while he is my six't. He is inexperienced, submissive and kind of boring in bed. Doesn't help that he is average at best and doesn't last very long most of the time.

I have a coworker, he is very kind, good looking and brings me coffee every day at work. So one day he asked me to come over. I told my bf and to my surprise he had no problem with it.

We started to meet regularly and he was always so nice and caring. We started watching Supernatural and I was scared so he put his arms around me.

It didn't feel wrong and I enjoyed the attention from him.

That turned into cuddling then into kissing and more. He is strong and knew what he was doing. And he is big, much bigger than bf.

I enjoyed it and I still enjoy it every time we meet.

My bf asked me why I don't want to be intimate with him anymore, so I jerked him so that he stops bothering me.