I am a horrible person.

I recently broke up with my boyfriend/friend of 4 years and now I'm being destructive, I'm seeing a guy who likes me and wants more but I'm using him for sex just to get my mind off of my ex. I know it's bad but I feel like I am lost. Will I ever get back to being normal? I don't like this Mike dude but I feel like I need to have sex all the time with him because he likes me. I don't even like Mike like he likes me but if I am alone I feel as if I might go crazy. On the upside at least he is helping me work out. I feel guilty and alone. I can't get my ex out of my mind. I can't sleep at night, but I have so much energy...?...What is going on with me?