Hi my friend ~ Honey, did you get any help after the rape? I think it's time for you to get into therapy, not only for the "drifting" in your relationship, but for the rape that you had to endure. I feel you have a lot of issues that you haven't faced yet, and it's time to talk to a professional and get these issues taken care of. A good therapist can help you with this.
Talk to your medical doctor and have him refer you to a good therapist. He will know who is best to refer you to.
In the meantime, you certainly don't need to be "drifting" or getting involved with anyone else because right now you have enough "in your head' to deal with. If you feel so inclined, you COULD take a break from your boyfriend, but that would mean moving out -- I don't know if you feel like doing that or not. That's your choice. I wish you the very best. I do hope you will get into therapy.
Please keep us posted as to what happens. God bless and please take care. Hugs, Lee