My wife, strangely, feels guilty over many things. Leaving me, the death of her father, being of mixed race, having acne etc.
I think it's possible to get over it. Probably takes time though...my wife's condition seems more serious, so she takes A LOT of time to get over anything...and probably hasn't let go of certain things, which is of course detrimental to one's mental health.
Don't beat yourself up over past actions. The illness is a major contributing factor for whatever things you have done before. I'm sure your hubby has forgiven you for anything and everything, like I have for my wife. If you still find it hard to let go, try praying to God. With God, all things are possible!