I feel like committing suicide?

Hi,I’m a guy and I been very depressed lately. It started back in late Febuary and has not stopped and not it is April. At first I thought it was just a phase I was going through, but it’s clearly not. I don’t know what to do? I feel like I become so isolated with everyone that mean a lot to me, like I use to talk to this one girl a lot and I’m going to admit, she was the only girl I would feel comfortable talking with. But I think I been “replaced” as friends when this new kid came to our school. I’m in high school so it affects me a whole lot. This is going to sound really sad and I’m afraid to admit in real life, but she only friend that is a “girl” that I talk to, that’s why it’s so devastating for me. Along with that, I think I creeped her out and when you creep girls out, you will always remain that type of person? I mean I talked to her recently and she says were still friends and I ask her why she ignores me at school and she says she doesn’t know and nothing is wrong. Like I use to flirt with her and she would do the same but then things just went downhill from there when I started to say I was going to kick that new kids ass but I never did because I didn’t want to hurt her feelings as a friend. And so then she stopped talking to me, etc. It’s been really depressing. Aside from all this, I have to worry back at home, with my parents yelling at me and my dad called the police on me several times. All for stupid things. I told I’m depressed and they are not helping and all they could tell me was, “your making us depressed!” and then they just snicker laugh. Then basically gave me hints that if I was to commit suicide, then nothing would really matter. Right now, I cannot rely on police because I hate them now really nor can I really on anyone. I don’t have friends to communicate to, I don’t have anyone, I don’t have a cellphone, I recently stopped being friends with my best friends because he does is smoke pot. I smoked pot too but I quit a while back ago. All I wish right now is for everything is to go back to the way it was, or at least get better and I do admit again, I do “love” the girl because what I need is support from her right now but obviously she doesn’t see that and she’s too busy with her new friend. And on top of that she broke up with her bf like a long time ago, last year and she says she doesn’t want want to be in any  relationship with anyone, but she told me I would make a good one for her and I think I creeped her out by saying I underestand but then I go back and do it all over again by just complimenting her postively on everything she has to offer. Now I don’t even know what’s going on. Now half the time, I don’t even know what I’m doing or saying, my grades went down from A’s to F’s. If I don’t have the motivation then nothing can happen. Please, don’t tell me to move on. I’m lonely, I have aquiantances. My parents will not support me in regards to entertainment or socially if you know what I mean? I wanna die really bad cause there is nothing worth living for. And again this is not a phase, it’s lasted way tooo long and please dont say i need a therapy as well.