Going against the grain here, I think it’s good to quit.
Obviously you should be objectively looking at the situation to see if it’s worth the effort to continue or not.
If you expend tons effort to accomplish something of very little value, did you REALLY win?
That being said, I’ve been homeless twice.
I also had 2 employees embezzle $100k from my current business and I persisted against that adversity—only to now be pocketing $18k/mo profit.
I also have a second business (PPC agency) in the works.
If you KNOW it’s worth it, and you KNOW you can do it, then why not continue?
But blind persistence is stupidity.