Can't move on

My ex and I have been broken up for almost 7 months now and for some reason I can't move on with another guy. My ex texts me every once in a while and we chat but it doesn't go any further then that. I've had a one night stand since him but for some reason I can't emotionally attached to a guy! Every time a guy asks me out I block his number on my phone and disappear. I've now gone so far in disappearing that I have thrown myself into work to make it impossible for me to go out and have a life! What do I do! I miss having a connection with someone!