I have two MIL's.
MIL #1- technically is DH's step-mom, but he calls her Mom. She raised him from the age of 3 and is the person he is closest with. I love her! get along fabulously. In fact, I think I get along better with her than I do with my own mother!

Just a wonderful and sweet woman. Raised DH to be a wonderful man, gotta thank her for that.
MIL #2- Where to start.... let's park the crazy train right here. She is DH's Bio-mom. Abandoned him at age of 2, she just walked out the door and didn't come back for 6 months. Then never really bothered to raise him or visit much. She would fly into town for 1-2 weeks every year as he grew up. Shower him with expensive toys and a vacation (she is VERY wealthy in her 2nd marriage) and then leave.
As a young boy he idolozed her. Thought she was just great and sophisticated because he didn't understand her faults. As an adult he really dislikes her. This woman *hates* me.
I think as DH and his brother grew up and were finally able to see her for the mistakes she made, she suddenly realized everything she missed. She barely knows them. At the age of 20 she suddenly started trying to act like DH's Mom. Demanding he do things as she says, and trying to control his life. He refused and she blamed me (we were dating at the time). MIL has repeatedly tried to break up our relationship, even tried to get our wedding called off a week before, said horrible things to DH and myself, and is a very manipulative human being. As she says, she is his mother and should come first above any woman! DH thankfully always stood up to her and backed me up. This even resulted in them not speaking for over a year at one point... until she agreed to apologize for her behavior.
Right now we have known each other 11 years. She is slightly more pleasant to me at the moment because she knows if she isn't nice DH will cease contact again.
We are currently afraid of how she will react when she figures out i'm pregnant. If it is a boy she won't care, won't even bother to know the kids name I bet. But if we have a girl we are afraid because she has always wanted a girl and has displayed very *weird* behavior in the past with little girls. DH and I have already agreed she will NEVER be allowed unsupervised with our children. We can not trust her, she is unpredictable, manipulative and vindictive.