long story short ... SIL told me about a forum she visit frequently (not here) and I decided to look it up. found her online as her daughter was her avatar pic and started reading some of her threads. she was online there for years and read loads of threads giving out/mocking/being disrespectful to everyone (MIL, her BILs, my dp, me, my other sil ... basically all her dp's family).
I told them and since then there is bad feeling. was i right?