If you feel like you're only doing things to live up to someone else's expectations then, you're not really living you're own life. The real questions here are : Do you love her and do you really want her back? If so, it shouldn't matter what your parents think. Your parents might be close to you, they gave you life, and cared for you all through adulthood but they should have no say in who you choose to be with.
In order to have a healthy and normal relationship with your parents, you should start creating boundaries and thinking for yourself. The only reason why your parents act this way is because you allow them to be strongly opinionated about your life therefore, they feel entitled. However, if you live with them or still depend on them financially in anyway, it ill be twice as difficult for them to accept these new boundaries. All in all, you're an adult now, take charge of your life and make your own decisions. Your parents should provide you support and unconditional love not manipulate you into doing what they want you to do.