Ugh. I lived with my parents for a few months last year. And they are wonderful people and wonderful grandparents and my DS and I are very lucky. However, it was terrible for me. I completely hear you. I felt like my relationship with my DS was detiorating while I lived there. Even though my parents would back me when I set a limit, or said it was bedtime, or whatever, I was still the one who had to SET the limit and their support of, "Mommy said it's bed time" didn't really help the dynamic.
I felt like DS stopped listening to me and he always wanted them. They became the fun/play people, and I became the constant nagger... time to get dressed, time to brush your teeth, etc. Before we lived there, I felt like DS and I were a team, in this life adventure together.
Some of it is the age/stage they are going through too.
I was lucky and moved back on my own last Spring and things got much better pretty quickly.
Hang in there and know that your DD loves you and knows you are there for her. Here are a few ideas in case any of them sound like they might help:
-plan special you and her time a few times/week. Build it up as special event if it's just taking a walk, reading books together, going sledding, baking cookies, etc.
-If you think she's old enough to understand, make a sticker chart for some behaviors that are driving you nuts if she's not listening to you. I had to do that with getting dressed in the morning, because he would immediately run into my parents' room and climb in bed with them 1st thing and it was a nightmare trying to get him dressed and ready for the day. The sticker chart really helped. He got a sticker for "no fuss no muss" getting dressed 1st thing. And he was really proud of himself. I started using that for brushing teeth, etc. At her age, you don't even need a prize other than the sticker probably.
-If there's anything you can think of that your parents can do to help, talk to them calmly when your DD is sleeping or not around. If they are not backing you when you set a limit or something, ask them to support you.
I hope some of this helps! Everything goes in phases with little ones... this too shall pass. And at least she knows how much she is loved all around. What a gift.