Maybe I'm just giving crap advice, but who's really missing out, you for losing a house because of your generosity or them for losing a parent because of their own selfish greed? One day, they may want to see you, they might miss you and decide they want to know you again, but they destroyed an entire relationship and trust because of what they have done. Then they will be the ones that are hurting, but it will be because of their own faults and they'll know that.

Sometimes the hardest thing is having to turn your back on your family to stop them from hurting you anymore, I know that. It's meant to be family, it's meant to be people that care for you and help you, not hurt, betray and take advantage of you. But sadly it's not always a nice picture. Think about YOU now, the resentments may be there for a long time but releasing an attachment from some people, as hard as it is, may be the best decision you might ever make, at least for you mental stability. I know it worked for me.