annoying

It's so annoying sharing a room with an older sister who constantly believes she's right or has a say in everything. I asked her if we could sleep with the light a tiny bit on, and her only excuse for saying no is that we switch beds, which she asked to do because it was itchy to her but not to me, and she has the audacity to say she asked to switch back when she never did. It's even more annoying because she sleeps with a blanket over her head, and as much as I care about her because she's my sister, she can be so annoying sometimes. Not only that, I got comfortable telling her that I've been feeling stressed and down lately, and she completely made a joke of it and blew it off, and then tried to talk to me like she hadn't invalidated my feelings, and I hate it because she makes me feel like this.