If the subject residence is now titled in your name along with your husband, he has an argument for claim to the property. If the title is in your name alone but you made payments from a joint account or he made mortgage payments directly, then he has an arguable claim to the property. You need to consult with, and hire, an experienced family law practitioner. There may be other factors to consider when deciding what property is or is not marital, as well as in determining how marital property should be divided. Trying to save money by not hiring counsel could cost you more in the long run.
Contact a divorce lawyer in your county. It sounds like you caused the home to become a marital asset, but you may have an equitable division argument. The 50-50 division may not be an automatic thing.
i think that you should get all the deeds from 2003 and 2008.
it may be that the piece you got in 2003 is your non marital piece and the piece you and your husband bought from your mom is a marital piece. the deeds will tell.
as the others have said, go see a good divorce lawyer.
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