I keep sabotaging my relationships on purpose :/

Not sure, but it may have to do with the erroneous idea that you aren't good enough for a relationship. Or, that you have trouble trusting people and so, to avoid getting hurt, you hurt first.

Check this out:

https://www.youtube.com/watch?v=iCvmsMzlF7o

If it's self-love you have an issue with, Dr. Brown's message is that you are good enough, if trust is the issue, her message is that nothing can happen without being vulnerable...

 

For me, the reason I sabotage relationships is that I don't think I can do better so I get really attached to someone and then they tell me how great I am and all of a sudden I jump to "I'm too good for them" and then want to move on because that person isn't perfect. Also I put way too much weight on the relationship: I want to be head over heels in love and when I don't feel like that I take it out on the other person, almost blaming them for not being perfect. So I have unreasonable expectations but low self esteem and so I often wind up fear-of-commitment-y.