I am not usually one, who just quits an argument. I believe there is always a way to compromise or find a way together. But recently, it becomes harder and harder to actually feel heard. Some things have to change for me here, as I cannot continue on like this.

Yes exactly. less css rules for somewhat dynamic style parts.

Thank you for these kind words. I also understand that so many others are having a harder time than I. Almost feels wrong to whine about it.
But I can't shake the constant feeling of exhaustion and lack of motivation.

The constant feeling of exhaustion and inadequacy don't really help. It's a deep spiral.

As the sole contributor to the project, that was more or less unavoidable.

I still think I understand what it is supposed to be doing. So there might be some refactoring evenings in front of me.