Mother in law is the worst!

My mother in law hates me....she puts up with me but it’s obvious she doesn’t like me. I have two kids 10 and 7 from a previous marriage but have been with her son now for 7 years (married a year). She doesn’t even treat my kids like grandkids and my sister in law is pregnant (we are so excited for her and her hubby!) My mother in law said “cant wait to finally be a grandma!” 🤦🏼‍♀️

Long story short, we announced we were due June 2020 and she said “well, not surprised...” How do you deal with these types of people and not let it effect you?