I am so sorry for your loss and for what happened.  Although you sis not say how far along the proceedings were and if your parents had entered in to a divorce agreement that was fully executed, the general rule is that you are still married until the divorce is finalized and so you are still entitled to inherit from your spouse's estate.  I know: it does not seem fair given the circumstances but I am fairly certain that challenging anything would only be a waste of your time and money.  But it may indeed be worth consulting with an estate attorney in your area just to be certain  and in case the agreement can be considered an executed contract.  Good luck.