In law RANT

so last week my MIL decided to text my husband f**k you and your wife out of nowhere. I had asked her why she was mad and she never replied. she hasn't been the best she smokes in front of me and my 4 year old and has seem to be picking up a drinking habit. Although I was never her biggest fan I never acted disrespectful to her even when she does towards me and my husband constantly. she seems to want people to feel sorry for her and has been causing drama out of nowhere and I feel like this is one of her stunts. every picture I share of my daughter she likes to screenshot it and put this exaggerated post on how much she loves my daughter and when my baby is born she is going to be just like her.😡 she doesn't ever come visit my kid or even call there is literally no effort what so ever! So here's my question should we let her know when baby is born? Should we make efforts to keep this relationship? And what if she does try to speak to us when baby is born because honestly I know when the baby is here im,not going to have the time or energy to deal with her crap!