IIRC, in the last episode of this soap opera, the mortgage was in your dad's name and the title was in both your dad's and your mom's name. It sounds like your dad got off title by deeding his interest over to your mom. My guess is that you are paying the mortgage that's in your dad's name.
If this is accurate, you have a big problem. You are paying a mortgage on a house you do not own. If something happened to your mom, the house would have to be sold to pay off her debts and the proceeds after the mortgage payoff would be split between you, your sister, and any other siblings. You are at this point buying a house for these people, not for yourself. In addition, your mom could decide at anytime to sell the house, and the net proceeds would be hers, not yours, no matter how much of the mortgage you paid.
I strongly suggest you take to heart the things that have been said here and on the original thread. You are not helping these people and you are hurting yourself. You have come so far from your first post here. Figure out a way to get out from under this mess and move on with your life.
ETA: What on earth motivated you to trade the Neon for a Saab? That's out of the frying pan and into the fire. Use some of the money you are pouring down the rat hole to get yourself a decent car. You work hard for your money, you have a lot of obligations, and you need safe, reliable transportation. And, because you are thinking of the future you, don't cut the 401(k). Instead, unload the family obligations and with each one that disappears, INCREASE your contribution by the same amount.