I know what you mean about her being infatuated, but personally , I wonder if it's more the lifestyle he's given her that she is in love with rather than him. I know she appears to have quite a miserable life, but clearly he has had money, whether it was his or his dad's, it's meant she can messaround on social media and call it work, rather than getting a real job. I think pre kids they lived quite a flashy lifestyle and their previous house was beautiful. I remember when they lived at the old house they both drove brand new cars, clearly through his dad's company. I think she met Steve and fell in love with what he had and could give her, the poor boys were her way of keeping hold of Steve