I used to bleach my hair almost every month and this is what prevented my hair from breaking off!
-Aphogee treatment- you apply it and wait til it dries. It will feel very hard and it somewhat "seals" any split ends together. this stuff is very strong and makes your hair sooo soft after you rinse out.
-LOReal professional Blonde shampoo & conditioner. It's in the purple bottles (Salon brand) it smells reallllly good
-Redken Anti-snap leave-in
-Nexxus Humectress
-Joico KPak treatment and Leave-in conditioner spray
-if you feel like your hair needs moisture, hot oil treatments help a lot
-if you're gonna use a hair dryer, straightener, etc, use a protective treatment before. I just use Paul Mitchell Seal & Shine