Your right, your inlaws aren't that nice.
My Wife's family have totally dropped her now since she reported a relative for abuse, her grandmother and mother both told her they wanted nothing to do with her and her sister claims she is staying neutral despite her knowing what went on due to personal experience.
Seeing how it pulls Megan apart is really soul destroying sometimes, so now that her mother has started speaking to her occasionally i've insisted megan has nothing to do with her because each time this relative that abused my wife comes over, she drops megan again and to be honest she only got into contact when she heard megan was pregnant again, asking if she could look after our son and have involvement with the twins when they come...over my dead body. I told megan if she really wants a so called relationship with her parent that is up to her but any children of mine are not going near her or her family because they are twisted. I've heard her mum say hurtful things to Megan, such as 'your making the abuse up so i'll love such and such a body less' and things like that and believe me there is worse, its not just denial its just downright evil.
Tell your wife to stand up for herself, she obviously has low self esteem and needs to learn that if her parents wont accept her as she is, an honest and hardworking mother then they should basically stay away from her. No one should have to run around after their parents just to keep the peace.