There are always things that alter relationships as time goes on. People are not static beings, you will do/say things that alter the relationship If your biggest fear (I think this is what I am hearing behind all this) is that she might end up having a relationship with someone else (& it certainly sounds like you don't trust yourself if you have cut yourself off....) you really should let her go ---- don't try to have an exclusive relationship when it is nothing but a cage for each of you-----
You are not in charge....none of us are....
I think it would be better if you could express your feelings (not wants/demands), your insecurities, and your hopes/dreams, share your interests with her, do things together, talk. Trying to control is extremely unhealthy for both of you.