What would you do

Ok first let me start by saying my husband has another child from a previous marriage who we get 4 days and 3 nights out of the week so we have 50/50 custody of her. When we first got together his daughter was 4 and is now about to turn 9. She use to be so loving and listened to everything you would tell her but when  I got pregnant and had our daughter things have changed. She's rude, talks back, tries to talk to adults like she is grown, she doesn't listen to me at all. If we do or say anything to her that she doesn't like she runs back and tells her mom and then we get a 26 page text from her telling us how we hurt her feelings and make her cry (because we said no, or asked her why she doesn't want to play sports) And her mom who is now remarried will text my husband EVERY single day about her, and half the time it's pointless stuff that doesn't even need to be talked about like for example: oh this time of year is when I found out that I was pregnant! Do you remember that?! Things like that.. It drives me crazy. Everything that goes on in our lives has to revolve around his oldest child. We can't go any where or make plans if it's going to interfere with her and her moms plans. Her mom texted me asking me to move my daughters birthday party up two weeks so their daughter could go to a wedding. And my husband doesn't see anything wrong with her asking us to do that. Well anyways all of the crap I have to deal with causes us to argue and fight. He told me I've changed since I got pregnant and blah blah blah. I told him yes I have changed since having our daughter but it's because nobody was happy that we were having a child. Not him or his family cause his other daughter was no longer going to be an only child and they didn't want her to feel like she wasn't loved anymore is exactly what his mom told me when I brought up the fact that she doesn't ever ask to spend time with our daughter but will call or text my husband and ask him to bring his oldest over so she can see her. And yet again he doesn't see anything wrong with that.. Well when I said that to him last night he told me, "no I wasn't happy about us having a child cause I knew how horrible my life would be". Of course that hurt me more than words can even say so I packed my daughter and I a bag and told him we were going to stay with my family 3 hrs away. After I left at 7:30 last night he never once called me or texted me to check on us to see if we were ok. And I still haven't heard from him today. Idk what to do or think... What would y'all do?