We recently built a house - on a piece of land adjoining my in-law's home (sold to us by them for a lower-than-normal price). I am quite a private person so I was a little wary about the location, but I am also practical and knew it would be the only realistic chance of owning a decent sized home of our own with a garden in a nice neighbourhood etc. We are very pleased with how our house has turned out and were careful to diplomatically broach the topic of privacy with my in-laws. This has worked out very well - they do come around to visit a lot, especially since we had DD (12 weeks) but it doesn't feel like they are intruding. They will often give us a quick ring beforehand, or check at the door that they are not disturbing us. Of course, we offer them the same courtesy and we all get along very well.
So far so good. The problem is my husband's sisters. I really like them, they are absolutely lovely, nice and kind, but they just turn up and treat our home like an extension of their parent's. One of them was here earlier, and whilst I was upstairs changing DD's nappy, she was downstairs rooting through our DVD collection, getting them all out onto the floor (which I ended up tidy up again!) and picking out some she liked, which she then told me she was borrowing. I tried to subtly let on that I wasn't too happy about lending them out (they are my two favourite movies, and she has a record of forgetting to give things back) but she didn't take the hint.
They are just very friendly people who probably wouldn't care a less if I acted like this at their houses. I am just different. I like to invite people around and make sure the place is nice and clean and tidy, and that I am looking nice for visitors etc - I don't like people just walking in and it makes me feel uncomfortable in my own home. I probably should have broached the subject with them before we started building as we did with my in-laws, but it didn't occur to me that they would be like this.
So, AIBU? Should I just suck it up and accept that it's part of belonging to a close family? Or does anyone have any ideas of how to tackle this? I am very reserved and non-confrontational, and really do not want to ruin an otherwise good relationship with my SILs. Has anyone been in this situation and found that they have adapted for the better after a while?
Sorry it's a bit long, wanted to make sure I included all the facts.