It's very interesting watching Liz unravel in these episodes, as she struggles under the weight of the great secret she's been carrying. Carolyn has grown up, spent her entire life living in this toxic atmosphere of hidden, buried emotions, lies, and secrets, so it is no surprise to me that she reacts this way. That is how many families react, for instance when a child becomes open about how they were sexually abused by a family member as a child. They don't want to hear, they deny, they will listen to anything that will immediately restore the (very unhealthy) equilibrium in the family. The person who wants to tell the truth is labelled the bad one.
Anyway, it's really sad to me that Jason can't just leave while he's ahead, or find a less intrusive way to blackmail Liz; he could have her buy him a house, and keep going to his job with a reasonable salary and be a parasite but far enough away for her to put it mostly out of her mind. All or nothing doesn't always turn out well.