<human>: I'm an 18 year old guy and my best friend is a girl. Our relationship used to be strictly platonic, and although I always wanted more, I was okay with the situation. We've loved each other for a while and we get along incredibly well, sharing all our secrets and what not.

Now, a couple of weeks ago we started having sex, and although this kind of closeness was something I'd wanted for a long time, she doesn't want a *relationship*, saying that she'd feel constrained and she needs her freedom to basically hook up with whoever she wants. Weird as this is, consciously I am okay with it – it's her life, plus we're both moving to different countries later this year.

I should be happy – we're very close and whenever we're together, everything's great, we're practically boyfriend and girlfriend. However, when she's not around and she doesn't answer my texts (even if I know she's asleep or at some party), I get really anxious. I can't pinpoint exactly what I'm feeling, but I've never been this anxious about anything – I even had a panic attack last week because of this. We talked about it and I wasn't even able to explain what I was feeling; I don't think it's jealousy. She's there for me and tries to help, but if I keep this up, I'll go crazy. Now even my positive feelings towards her – such as love – are sort of overthrown by anxiety or whatever the hell this is.

I am considering therapy, but I would like to solve the problem myself if I can. Right now I'm reading "How to Love" by Thich Nhat Hanh (Buddhist monk), but I don't think a book will be of much help.

Please give me some tips. If you've ever been in this situation, let me know how you were able to get out. I would've never thought I could get so anxious about something and it fucking hurts.

Thanks.

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<bot>: Anxious when FWB & best friend isn't around, can't tell why. Need to get rid of negative, destructive feelings.