I think bpd2 has a pretty good idea. You can be there with her even though she is sleeping.
Her sleeping pattern is all about accepting her and who she is. If it is bothering you that much and you are resorting to cutting, maybe you should talk with her about her sleeping and see if adjustments can be made. If not you might want to re-evaluate your situation and the relationship. I know it is hard but you have to take care of YOU first!