Sunk-cost fallacy is the phenomenon whereby someone may not want to give up something (or someone) because of how much they’ve invested into it, even when the better course of action would be to abandon it. But it’s okay to start over from scratch. You may find yourself coming out the other side realizing how much better off you are.
I quit my “dream job”. It felt so discouraging to let go of something I had wanted so badly. Now, I don’t regret it one bit.