<human>: Can you condense the text into three sentences or less?

I'm a lesbian for reference.

My girlfriend (22) and I (22) have been together for 3 months. I really like her a lot and want to continue this but I feel like I'm pushing ourselves apart. We've moved really fast and see each other about every day. We both know this is unhealthy and have discussed taking space but when she says she's staying home for a night or going out with friends instead I get a little jealous. I know it's what we both need but I can be a little selfish and start to wish she didn't want to be with anyone but me.

 When she's with her friends I start to get paranoid wondering what she's doing which is crazy because I don't think she's cheating at all. I just think that sometimes she wishes I was someone else (like the girl she fell in love with in H.S.) It's could be all in my head considering I tend to let my past relationships where I've been cheated on and hurt a lot effect this one. 

Whenever she's with other people I get the idea she's partying and doing drugs or something else stupid. I know she used to smoke weed which I hated but she quit. Sometimes I think her friends will get her to do it again. Sometimes I think they're just sitting around talking about how crazy I am.

 I know this is bad for us but I don't know how to control it. I don't want to act this way because it leads to us bickering about little things. We get into insignificant fights and in the end I feel dumb for hurting her. I know she won't put up with this much longer.

 Do you have any advice on how I can be more understanding and less paranoid? Or how I can handle the situation without causing a fight?
<bot>: I'm selfish and get jealous when my girlfriend is with her friends. Leads to fighting. How can I stop this?