Plagued by constant thoughts that I need to break up

My girlfriend and I have been together for about 3 years. We have loved together for a little over a year. I would say for probably the last 8 months I have been constantly preoccupied with the idea of breaking up with her. I constantly think about the freedom to be alone in the house, do things my way, have great sex that I really enjoy with a variety of people. It has gotten to the point that I am physically and mentally exhausted from thinking about it. The main reasons I can articulate for wanting to break up are: 1. She wants to move to another city in the next year or two. Up until now I have been on board but it has recently occurred to me that I do not want to move. I would like to stay in this area for at least another 5 years. 2. We are not a match sexually. We met in the BDSM world and initially had some mutual interests but it has become very clear that the things we both love sexually are not things the other is interested in. Sex has begun to feel like a chore for me. 3. I think that I have a lot of travelling and adventure in my future and I would really like to do it as a single man. 4. She tends to be negative towards my ideas and opinions, and sometimes it seems like she disagrees with me just for the sake of disagreeing with me. The catch is that I truly do love her. She is without a doubt my best friend. Every day I see her do something that is so cute I could die. We do have fun together and make each other laugh like crazy. We also depend on each other a lot for emotional support. Being with her has shown me the powerful impact an intimate relationship can have on one's life. But I feel like there is no way I want to be with her for more than the next year or two. I will explode and go do something stupid like cheat because I feel so trapped. It just seems like maybe I have to accept where we have shortcomings in our relationship and work to improve them? Is this fantasy of single life misleading me? Will I regret breaking up with her because I could have more work in and made it work? I don't even know how to break up with someone you live with. Oh man the idea of hurting her breaks my heart so much. I know this is a bit of a ramble, but any feedback is appreciated. Thank you

It seems like you have a made sex an idol in your life, meaning you will do what your sexual desires want you to do. I don't mean that to be harsh, but if you truly are in love with your best friend then you have found something that you would regret throwing away. Reading between the lines, it really is just all about sex and that is what you need to honestly face. You need to be truthful to yourself first. Secondly, if you do love her the way you say you do, you need to be honest with her because each day makes an eventual break up more difficult. Sex should not be about sex but about love. If you love her the way you say you do, no sex could ever be better. I would suggest you re-evaluate yourself and your sexual desires.