That is my fear as well, but one can only take it one step at a time.
You should only undertake it when you are ready for it, it is a choice. Yes, I didn't exactly have a choice for when my guilt came crashing over me, but it was a choice whether or not I faced it. I didn't think I was equipped for it either, but life has a way of giving you unexpected things and ways with which to help you.
I am perhaps one of the least patient people in the world, but I am undertaking this, trying to change. But when given the proper motivation, the level of patience you have does not matter.