<human>: Before I get in to this, I want it to be known that I love him, and I deeply care about his happiness.  We bicker quite a bit though and recently my be has become a jealous person who often gets mad at things I can't control (like if a guy texts me out of the blue).

Now, hers my problem, I'm 22 years old and I can't stop thinking and fantasizing about my life without my SO. 
I've recently lost all want for sex with him and I'm wondering if maybe my mind is just wandering? 

I'm especially intoxicated with thoughts of a previous fling I had (let's call him P) years before I met my bf, although I was still talking to P right before I got with my boyfriend (as friends but with some flirt). And suddenly, I can not stop thinking about him, he even jumps in my mind when I'm masturbating (this brings so much guilt, especially when ya thoughts of my time with him that makes me reach climax).

I feel incredibly guilty and I know my boyfriend can tell somethings up but I just can't stop thinking of P, or my life if I wasn't with my bf.

It's not just that though, at times I really miss being single and I feel like my life would be filled with more exploring and spontaneity if I wasn't with him.  

Has anyone ever felt this? Is this just a thing I'm feeling that will pass? Or am I truly over my relationship? 

When I think about my future, I'm afraid that if he's in it I won't do the things I want to do in life. But when I've talked to him about this he assumes it's because I just want to be single and sleep around which I don't, I just want excitement again.

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<bot>: I have had fantasies about a life without my boyfriend. Don't know if this is a phase or if it means I'm not happy anymore. Need advice.