Need advice

So Ive been talking to this girl for a little over a year now. She knows I've wanted to be with her for a long time. We act like br and gf. She even refers to herself as "my girl" sometimes. But other times when people ask it's "I'm not his girl". We do the stuff bf and GF do. Treat each other and take care of each other's needs. But then she disappears for days totally ghosting me. I used to blow her up a lot more than I do now. I'm trying to accept that she needs her space. Lately she keeps leaving to this other guy's house any chance she gets. She claims that I'm the only one she lets touch her, and that he's just a friend. She seems emotionally invested in him. She keeps promising she won't leave and saying things like " he has his kids tonight I can't go there" and then all of the sudden when he's available it's " his baby mom grabbed the kids I'm going to his house now". Or he's working a double shift I can't go there I promise then end up going there anyway. I find myself begging her to stay and her feeling bad agreeing and ends up leaving anyway. I end up getting mad and telling her not to talk to me any more and blocking her just to unblock her a day later and try to get her back. We are stuck in a negative cycle. Sometimes it's a good time but other times we try to communicate each other's needs but it feels like picking each other apart and turns into an argument. She says I'm exhausting and she just wants to be friends but expects the benefits of a girlfriend. Calls me baby kisses me on the lips sleeps with me. I guess a title isn't that important but she offers me no security. I've caught her in lies about other men many times. She says she has to lie or I won't let her leave but she leaves when ever she wants anyway. It's gotten to the point I'm so paranoid about her texting other men I worry when she goes to the bathroom. She uses my wifi to use text now on her phone. I've unplugged the wifi on her multiple times because she texted a guy non stop for 2 hours straight while at my house. I told her I don't want to feel like a pit stop that she uses to wait for him to get out of work. It makes me feel like I'm nothing to her. She says she loves me and I'm doing everything to show her I care. I even quit drugs 3 weeks ago which was for myself but also heavily inspired by her. But I'm still acting the same kicking her out when she runs off with her " friends". I haven't talked to her in days and she found somewhere else to live for now. I'm trying to focus on myself and get better so I can live without her and not go crazy. I get that I put a lot of pressure on her with the relationship stuff. I don't want to lose her. Any advice?