Abomination's a challenging battle, but it's doable. There is better food in the game than stamina drinks (e.g. Your Milk then Angel Milk, or just Fish Soup (Good!)), make sure you have good weapons equipped, get the usual set of stat buffs from town, and be sure to Guard for the big attack rather than outhealing. I was able to beat it (18 str, 11 res post-buffs) without using any healing items and with really bad strategy, so if you have a few you should be able to do it when weaker than that.