In every venture, you need to have a ceiling. That is why you need a plan, so it will let stay on course and not veered off by some tides. And in the plan, you need to know that if this goes into this Nth degree, you have to stop and think of a way to sway it or start again. Do this first before starting it out.
It's not about you giving up, it's a matter of how many times you get back up.
Basically right now you probably don't know when to give up. My advice for you is to take a piece of clean paper, divide it into two with a marker or pen, then do the brainstorming. On the left side, write YES and on the right side NO. Then at the top, write your question.
Ex: "Should I continue doing this?"
Spend as much as time you needed to think through everything, until your brain bleed out. On the YES side, write all the benefits, pros, advantages. Then on the NO side, write all the losses, cons, disadvantage.
Once you're done listing everything, now weight it in. I'm pretty sure by now you'll get a clearer picture on what you should do.
"Should you give up or should you just keep on chasing pavements?" ~Adele
Hope this helps!