Let me add another thing. He is out with the boys every day and every might I never get an invite and he's always at parties and I never get invited either.. he's changed so much
I am not certain you are over-reacting. I think you may be responding to more than his finding other females 'hot'. Based on what you wrote, I get the impression you are starting to have doubts about the relationship and/or his commitment to it and you.
If he spends so much time with his friends, how much time are you spending together? Has he ever given you are reason for not inviting you to the parties? Is he putting enough energy into the relationship to keep you from feeling like you are the only one trying to keep it going?
I think it is time for you to take a long hard look at the relationship and see if you are getting what you need out of the relationship. Then you need to sit down with him and discuss what each of you expect from the relationship. Together, you need to decide where your relationship is headed.