I don’t know how to take breaks...

I really need to figure out how to take breaks. I’ve realized I’ve been so frustrated with my husband because he can sit down and play video games or play on his phone and not be worried about our daughter, but I can’t do that. So I get so frustrated with him. I want to be able to disconnect sometimes, but i don’t feel like I can. I am constantly worried about, listening for, or watching our daughter. It sucks to because I’m also the one that is working because he is a full time student. He does chores around the house and occasionally makes dinner which has been helpful, but even when I am “breaking” I’m working. I never seem to be able to let go of the endless responsibilities I have. I brought it up to him and he said it’s something I have to work on and he can’t help me. How can I learn to disconnect and get more me time?