I just can't end my toxic relationship

I ALWAYS GET THE BLAME...

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EVERYONE says that me and my bloke should split up.

We row all the time. We cheat on each other and have no trust.

My sister describes our relationship as a “car crash”.

She believes we thrive on chaos; that we're on a negative downward spiral headed towards ruin.

She keeps begging me to break up with him before I fall so far I can’t get up again, but splitting would be so hard because he's all I know.

Yes, I admit our relationship is unstable and toxic, but what would I do on my own?

In his eyes, nothing I do is right. He blames me for all the bad things in his life (his dysfunctional relationship with his parents, his poor pay and horrible job). If I break something in the flat - a mug or a plate - then he goes crazy calling me clumsy and useless.