2. Go On One Ridiculous Bender
You can go on one ridiculous drinking bender (which might be what you've been doing as of late) but that's it. Just one. If you turn into a sloppy drunken mess than he wins, and he does not deserve to win.
1. Be OK Just Being Yourself (or Pretend)
Dye your hair, get a new wardrobe, put out a new album, or do whatever it is you need to show that guy that you don't need him. Wash that gunk out of your hair! Moping around in a rehab facility just allows him think that he still has control over you and that's not what you need. Rihanna, you should be looking like she is having the time of her life right now. I know that it is cliché, but laugh really loudly at some other man's joke when Chris is around. Be seen out on the town with your girlfriends looking fabulous. Wear crazy hats because that's what confident women do. Then go to Africa or something and help hungry children and smile really big for the cameras, so he remembers that you are the nicest person in the entire world. Hey, you'll be helping starving kids. Bonus.
You will survive. We all do.