Death and divorce the same day?

my niece and hubby were in divorce proceedings, and the degree was issued but not signed by either party, because she wanted to appeal the divorce. He died that night. he had made a will with everything going to her and hers going to him. they had appointed his friend (future girlfriend) as executor if either one of them was unable to be executor. When he died the girlfriend cleaned out his place and claimed everything. They were not living together. can she be charged with theft and is my niece the widow or just SOL they have a 10 yr old daughter together.