Oh my goodness @Arraminta@Hagr1d : same!
My MIL is the most immature, childish, selfish, odd, strange, silly, racist, sexist, two faced, bitchy , emotionally stunted and repressed, cruel , manipulative, cold, fake, self isolating, never takes any personal responsibility, treats her adult sons like little baby boys (yet has never kissed hugged or told them she loved them in her life) she's horribly jealous of other women. Mortally possessive and controlling of her sons. Lacks all empathy for others , especially females. She acts like a 12 yr old boy (yup, seriously) talks in a baby voice.... God I could go on and on.
I've tried so damn hard with her. To understand her. To give her a million excuses for why she behaves so oddly.
I've killed her with kindness and my face aches from being so nice to her (it's paid off. Mostly ) but I've had to sacrifice my sanity at times and let her get away with way too much in order to keep up the "we're friends" facade.
Very very few people have any idea how much I resent and loathe her (and I was very much willing to try to like her ) now I meet her complete lack of effort and empathy with minimal effort back (whilst still being nice ) sometimes I have some very unchristian thoughts about her.