DAE feel in the relationship that you need to take care of two people while they just need to take care of themselves?

I'm 29M and my partner is 29F. Whenever we spend time together, I feel I am doing most of the care work, in terms of cooking and cleaning, chores, travel planning. Our situation is a little complicated since we are long distance and she works while I am a grad student. So when we get together I am usually the one with relatively more relaxed schedule so I thought it made sense to do the majority of the care work. However, it can be draining both mentally and physically. Right now I am really busy so when we talked about planning a trip for Christmas I suggested she could do the planning. She outright refused because she says her work is busy as well and I am usually the one to do it so I should still do it. We went back and forth and she ended up being a little upset. It just feels she uses me as someone she can unload some of life's pressure while I feel extra pressure when I am with her because I am taking on her share. She contributes when she wants to or when I really ask, but the default position is always me taking care of everything.