My mom is mad that I'm pregnant

When I was 16 I got pregnant. My family tried to force me to have an abortion but I personally couldn't go through with it and have the baby up for adoption (the paternal grand parents adopted the baby). When I was 19, I was raped and got pregnant, again giving up the baby for adoption. When I was 24 I got pregnant again (unplanned) but because I was older I kept the baby. I'm now in my mid 30s, have my college degrees, married for 5 years with a house, cars, and both have very good careers. My husband and I planned our pregnancy for a couple years and are elated to be pregnant. Everybody is except my mom. My mom couldn't be more furious. She wants nothing to do with the baby. My MIL is throwing us a baby shower and not only did my mom not offer to help, she's not even going. Her reasoning is that I should have tried to build a relationship with my first two babies instead of getting pregnant and that she's upset that I won't publicly admit that I had two babies up for adoption. I'm so morally torn. It's really starting to stress me out. I don't even know how to reply to people who ask what's going on with my mom.