Look.. I need help :(

Has anyone been a relationship that they don't want to be in anymore but haven't got the strength to leave?
I can't stand even having sex with my SO, or kissing them.. They have hurt me to many times in the past we have been to gather for 3 years next month.. And I will never be able to forget it .. I always dream about leaving them.. But can never have the strength to do so..
Sex is just a chore to me .. 
Sick of the abuse :'( am I not alone in this?