have you tried heat massages? also where does it hurt? along the flat part of the wrist (as in when you have your arm on the table, the part underneath), or along the sides. if its the flat part of the wrist (palm side) then its more serious than the side. wat did the doctor say? ligament damage? if so, it will take alot longer to heal, and since the wrist is such a moveable joint, it might never properly heal.
i feel for you, cause i kno exactly that your going through, the frustration of not being able to do even a single pushup. i would start off by taking glutamine powder, and extra protein, to help in the healing process. also maybe just do some daily exercises. like non stop fist clenching for 2-3 minutes (might sound easy, but try it for 1min..). this helps. also basic wrist strength exercises.
sorry thats all the advice i kno may work, cause thats all i did when i injured my wrist. (apart from having it bandaged up tightly for the first 4 weeks, during which i did NO exercises on it)