Getting better?

So, I really don't know what to do:
I like this boy but i know I still have feelings for my ex. I feel so wrong going into a relationship if I know I have feelings for more than just the person I'm with. On the other hand though, the boy I like now helps me forget about my ex. When I'm talking to him I totally forget about everything else but then when I'm not the only one I can think about is my ex. I have no idea what to do. Should i just stay single until I know for sure I'll only have feelings for the person I'm with? OR should I just try a new relationship even though I'll feel guilty? It's all just so confusing.

Does any one have any advice for me.
Especially how to get over someone?

Thanks, Chelsie.