That's right, and she has done nothing but take care of your home and bear and raise your children, responsibilities which have no value? SHE is so miserable that she has left you twice and with a 15 week old infant, have you ever heard of post partum depression? Were you together when you bought the house and did you intend to raise your family in that house with her, when you bought that house? You do realize you are going to get stuck with child support?
Michigan is an "equitable distribution" state, generally meaning that all marital property acquired during the marriage is subject to division. Property brought into the marriage i.e. that a person had before the marriage are not subject to division in a divorce, unless you have given her that right when you refied, so she may be entitled to at least a portion of the value of the home and possibly even spousal support for a time since she was not employed outside the home.