GF issues (crossposted from journal bc idk how this site works)

tl;dr my girlfriend makes and posts content that I really really don't like (and she knows i really don't like it, and only got into it *because* i told her i don't like it) so i tried to block her socials so i didn't have to see it but she got really mad at me

I'm so stressed out and emotional over my relationship. I feel miserable in it and I want to break up with my gf, but I can't because she made me promise not to and she gets so upset whenever I'm not happy in our relationship. 

There is certain content that triggers me to the point of tears/hyperventilation, and *after* I told her this content upsets me (she never knew about it before me telling her), she became a very big fan of it, making drawings/an animatic concerning it and frequently "liking"/reblogging posts that concerned it. This happened about 3-4 times, each time with me breaking down. I downloaded an extension onto my computer to block it as best I could. However, when I scrolled her socials today, I found graphic incestuous art (naked, kissing, etc) that she liked, which was the biggest thing on my "no" list.

I was shaken to the point of tears by this, which was, again, probably the 4th time this happened with my girlfriend. I decided to block her social media (but not our text thread, how we usually communicate, so she could still talk to me). She blamed me for it, said that I had no right to break down when I had hurt her more, and essentially fell apart, saying she wanted to hurt or kill herself. She called me 'emotionally toxic' and stopped talking to me.

I understand that it is dramatic to be so deeply hurt by content. I am currently dealing with crippling mental health issues that make it difficult for me to think straight, and as such I've cried several times when she sends me content, relating to different topics (I have cried over three video games, a fanfiction, and several pieces of art she's sent me for different things). However, I am working so hard to be better for her. Every single day I try my best to keep it together, and provide her with love and affection. Even when I can barely get out of bed, I try to put a smile on my face for her.

Historically, she has viscerally hated content I have made, and made me change it to suit her tastes. I work harder than I ever thought I could for her. I am out of energy and out of love for her. I haven't loved her in a long while. I just want to keep her happy. I want to leave her, but I can't, because of all the times she's made me promise not to. Because I've changed so much for her, it feels reasonable for me to request one small thing. And I'm not even asking her to stop liking incestuous content, even though it disgusts me. She can do whatever she wants when it's out of my eyeline. All I wanted was to block her socials so I didn't have to see the content, but that just got me in trouble with her.

She accuses me of not trusting her, but she lies and hurts me so much it's hard to trust her at all. She promises not to lie to me, and then lies to me. I am out of strength to deal with her. I feel like I just have to be this perfect stepford wife so that she can be happy. And I feel like I can never ask anything of her, even if I'm not asking her to change anything and I just want to not have to see things that give me panic attacks anymore.