Going Crazy!!

OK so I met this girl on a mmorpg whilst drunk and rambling, I happened to get into a Skype with one of her guy friends, and low and behold she was in the call. :s... Anyways I didn't really know her at the time.. So I was kind if an asshole at first.. Starting off the conversation with " who the **** is this chick" I could tell she was kind of shy and nervous to hear a new voice so she didn't say much, anyways as days go on seeing her on this game I wanted to get to know her more, so I hit up a conversation.. Okok this goes on for a year. We chat daily, on and off skype. We exchange Snapchat blah blah.. We fight, we make up.. But I feel like I've fallen in love with her and I know she doesn't feel the same way, that or I'm really blind..I haven't really expressed my inner most feelings for her all because i have this tough exterior and showing people I really care is like pathetic or something. So as time goes on I don't message her all because I have I literally hate starting conversations.. But in-reality I wanted too, so I'd constantly wait for her messages first, and oh believe me.. My face lit up when shed message me. But I notice I became nervous and started to over analyze everything and became afraid of what shed think of me.. A totally new feeling to me btw...Its like everything I said had to be perfect. I'll save you all the details . OK so current day were really good friends, but I've noticed I become angry when she doesn't message me back instantly.. Like she's talking to some other guy and that she's taking a liking to him. And when I see her online on skype I can't even control my thoughts about what's going on..I know this is extremely jealous.. But man its killing me inside daily for almost a year now... And when I get upset with her I tend to get reckless and binge drink/drugs and ignore her while thinking about her the whole time..like she's gonna come stop me or something.. But eventually I logg back into Skype with countless messages like "are you ignoring me?" Or "are you there??" Are you made at me?" Plenty more... So I guess my question is.. Would it be super fucked up and selfish if I were to tell her we couldn't be friends anymore without any explanation.. Because like I said I can't express my true feelings.. Its who I've always been.. I just can't continue on with sleepless nights and waiting for that message to pop up once again on my screen.. I feel hopeless on trying to win this girls heart... I'm a kind hearted person with a gentle spirit its just I keep to myself wayyyyy to much. I'm very introverted and antisocial.. Its just deteriorating my mental state and I've noticed... She's my poison and I'm addicted... How should I deal with this ughhh I need help ....