My stepson has becoming increasingly resentful of me over the past year. He is my husband's only surviving son of his first marriage long ago and is 40+ years old. He drinks more than he should and has not been able to find a job in nearly 5 years. I've helped him move from an apartment, search for a house, move into the house (that his father bought for him) and even drafted a resume to help him find work. We joke around quite frequently but without warning he will lash out at me and catch me off guard. I have never been hateful to him and don't know where this is coming from. His father is older than me (I am only 5 years older than my stepson) and the son has made it clear that if anything happens to his father, the house we live in is his so I can forget about it being mine. I've tried to talk to him and have made an effort never to come between them but it's not getting any better.