My major cause of breakage was dryness - and the very very far second was strength. I used to go a buy every shampoo and conditioner that promised "strength" - until I finally figured out that all the extra protein was drying my hair out, making it MORE prone to breakage. I experimented until I found the right moisturizer and method, and I stick to light protein. My products are:
a spray I make -
2/4 100% Aloe Vera Jelly
1/4 vegetable glycerine
1/4 filtered water
and about 10 drops of grapefruit essential oil for scent. I will spray this on first to dampen, then use a creamy moisturizer like Lacio Lacio or NTM.
I seal with an oil mixture ( also in a spray bottle) I don't know the parts, it's Jojoba, Peanut, olive and ginseng wonder oil all together - the ginseng oil smells really good so I use a little of that and alot of the others. I will sometimes ( like at night ) seal with castor oil instead. I notice that when I use this I don't need to remoisturize every day. Make sure you hit you new growth AND your ends. The difference in texture causes breakage high, the dryness at the ends causes breakage low.
1 more thing -- try mixing glycerine and honey into your deep con. They are great for helping hair retain moisture. Wear your hair up with ends tucked, comb VERY gently. Get a baby soft brush -- if it hurts to brush your hand don't use it on your head -- and airdry whenever possible.