Someone please help

Ok, I need some honest opinions. I have been dating a guy for four months. We went to high school together but never really talked. We went out early last year a couple times but I didn't really like him. Later last year he asked me out and we really hit it off. In the beginning he was everything I wanted .. and more. He made me feel like the prettiest and only girl in the world. Recently, I feel like he is just changing. We are very different. He is a lot more outgoing than I am but I feel that opposites attract so its not really a problem. We have different opinions on quite a few things but have decided that is something we can get past. He has a very cocky, hateful attitude at times and I talked to him a while back about this and he said he was sorry and he'd try to stop. I feel like since, he has changed it some, but not completely. He has always told me from day one that he will take me over anyone, even his friends. When he first moved back home from college, his high school friends didn't hang out with him much, but now that they are, I am seeing him less and less. Used to, when they wanted to see him, he'd ask my plans first. However, last week, he cancelled our plans to see them. later, they cancelled so he changed his mind and then wanted to see me again. This REALLY hurt my feelings. I didn't see him that day and told him I was really hurt. He said he couldn't just tell them no since he has a girlfriend (?). Now they are hanging out every sunday evening (as well as some during the week). I know that shouldn't be a problem but me and him see each other during the day on sunday and when it's his time to see them, I just have to leave. This makes me sad. I don't know if I am jumping the gun? I know he needs time with friends. My family and friends said this is the weirdest thing they've heard...they said a guy should want to spend time with his girlfriend over spending it with a bunch of guys. I see my friends too but have never cancelled me and his plans to do so. Also, recently, he has been pointing out how "hot" celebritites are in different movies we watch. When he does it, he will look at me and grin. He loves it when I show that I care by getting jealous. Normally I am not that jealous but it kills me when he does that! I know guys will always notice things like that but to me, it is a respect thing. He knows I don't like it when he points that out. I act jealous and he will say Im just kidding?! but then when I act like I don't care (in hopes he will quit), I say I don't care anymore...Im so used to you saying that stuff. Then he will say "well that's not good (that I don't care anymore). I started pointing out hot celebrities too to make him see how I feel and he gets extremely jealous when I do so I don't see why he would do it to me. This probably sounds childish but I don't care if he thinks someone else is hot. But to sit there and talk about it repeatedly is just disrespectful in my eyes. We have been arguing a lot lately, over petty things and its made me lose a lot of feelings for him. I do care about him though. I don't know if he's lost feelings for me. To be honest, I don't see how he couldn't have. We argue .. a lot. He thinks he is always right and that doesn't roll with me so we usually end up disagreeing. Nevertheless, he tells me he loves me more than ever...I just feel like he doesn't prove it. The thing is I care for him but just don't know if it's worth it anymore. I want to break up with him because a small part of me thinks if I do he will realize what he's lost and change and maybe one day we can work it out. A small part of me wants to say goodbye and never look back. It's just not that easy though. I'm so afraid I will regret it if I breakup with him. I just feel like used to, he made me the happiest girl and made me feel like the only girl in the world. I no longer feel that way. Sort of want a break from him, but don't want to regret it. Someone please help. Everyone close to me that I ask for opinions all I get is "that's a decision you have to make."

I can relate, I think what is happening is quiet common , it is gone passed the honeymoon phase , it happened quiet quickly, which is natural enough when you are young. I can sympathize with the comments of other girls to deliberately upset you, you are correct it is disrespectful , why do guys do that? I think you have outgrown this relationship? If you are going to end things do it for you, put value on yourself, you deserve to be listened too, and your feelings taken into consideration. If he don't call you back after you break it off then you are well rid. I think some time on your own and enjoy life with a guy in it will be good for you. If you put value on you so will others..... keep that mantra in your head. Hope things work out for you