5year old

So I need some advice on what to do! We have a 5yr old daughter and just had our second little girl on the 4th of May. She is great with her and loves her so much. The issue is with me. I'm a stay at home mom and the baby of course is with me 24/7. My older girl acts now like she absolutely hates me or something. It's always been just me and her forever and now it is not. She keeps saying things like "I wish I lived with Mimi and not you" or just talks back to me really bad, throws her little fits, stomps her feet, walks off and says "FINE I guess I'll just be by myself" or little remarks like that. Is this just because she's jealous or something else? I really do try my hardest to play with her as much as I can. When baby falls asleep We will play barbies or shopkins or with her play kitchen. Even when baby is awake and on the play mat we all get on the floor and play dolls. BUT as soon as baby starts crying my daughter will say "so now we aren't gonna play anymore?" I just don't know what to do anymore. Nothing I say to her does anything and she still keeps talking back and all that. What do I do please!