is it alright? and how do i stop this?

i have been with my girlfriend for almost 2 years now. we have had many problems recently, fighting, jealousy etc. we both have our equal faults, we are both wrong in many ways but right at the same time.we are equal, im very confused because other then that there is one thing that she is doing that im not.. theres another guy, he used to be my friend but not anymore. he met my girlfriend when i was with her and he started to talk to her, at first i thought he was just a good friend helping me out but gradually he started to gain feelings for her while me and him where friends and he told her that he likes her but told her not to tell me, in the end she told me but i didnt say anything, i let it go.

over time months and months past, me and my girlfriend were fighting about something and he joined in and told her that she deserves better along with other stuff, i took it to affence and had enough so i told him i dont want to be mates with him anymore because thats not what a real friend would do. he tried telling me that he just wanted to make her better but after the first time i couldnt trust him. i no he has feelings for her but he wont admit it.

as now they are really good friends, he really likes her because he has told someone that is really good friends with me. not just because of that but because of the way he treats her, when we are fighting hes always there to pick her up, always calling her, calling her cutie (pet names), flirts with her but she doesnt understand because she thinks hes just being nice. he has let her drive his car which is really fast and i dont approve of it because she hasnt even got her licence, he went out of his way to pick her up from work recently because we've had problems, from far away places etc. it really hurts because theres nothing i can do, i no im better then confroting him and having a fight. i no hes not worth it but how do i tell my girlfriend this? i no if me and my girlfriend ever broke up for good that he will go for her!

how do i tell her its not okay what shes doing because it really hurts, its not like he is any special, hes just nice to her and she seems to like it. i dont no what to do because no matter what i say she always seems to find her way to speak to him, not because of her but he always tends to say hello and talk to her. im not as jealous as i used to be but i just think its unfair for her to have someone this close to her, someone who is completley in love with her and i no it for a fact after everything hes done for her.

im not scared of her going off with him but i dont like the idea of people always ringing me up asking me why she was with him, why hes always with her, they've seen her get picked up by him, are you and your girlfriend still together because shes always with him - i mean its crap because ive never done something like that. i trust her but i dont trust him at all.

im very ensecure because hes just always there! i dont no what i can say to her for them to stop speaking to each other. i no hes not a good friend towards me or her because he once rang up my girlfriends mum and told her that i spat on her after we just had a little fight, her mum believed it and said if thats true then im not welcome in the house ever again! thats how i no he loves her because why would someone make up something so ridiculous?

any positive advice, what can i do about this? how can i tell her to stop talking to this guy? i no bad things about him that she doesnt no and it seems to me when i tell him to stop talking to her, he looks like hes about to cry and seems like oh crap why why, why cant we friends so and so..

i really hate it, any one please help? what can i say to my girlfriend because i cant go on like this? it hurts alot! i just want her to stop talking to him. they can say hello just not be bum buddies.

please help? any advice that could maybe stop them from talking as much..