Of course, she hates you.

Basically she thinks you have ruined her happy life, which I believe you did. The mentality of what you just bought can be a little cheaper from another store is not going to help you to establish any bound with her. I guess you were not ready to be her step-mother when you got married. And you still don't understand it. All you care about is money. Of course, finance is important. But as long as you guys can get by, no savings is not such a big deal. From what you described, I do believe you are the reason that she is what she is now and she has every reason in the world to hate you.