Thank you all so much for sharing your stories here. I've slowly been going insane, thinking I'm the worse person in the world for the struggles I've been having as a SM. I thought it was my own jealousy and insecurity that made me react badly to the actions of my SKs and even my DH, but I'm learning that these things are actually quite common for blended families. It nice to know that I'm not just overreacting to our situtation, and that it is totally OKAY for me to expect certain boundries and question things that make me feel so uncomfortable in my own home.
Just found this site and very excited to find some people that have grappling with the same issues as me. I've been a SM for almost 4 years now, and it seems to be getting harder and harder for me to deal with it. I have no close friends that have skids, so no experiences to learn from other than my own upbringing (which was less than ideal!). My skids really couldn't care less about my existence. Their BM is a jealous and pathetic woman (she really is a nightmare), even though my DH and I have bent over backwards to make our situations work as best we can.