Your writing standard suggests you would handle college/university no problem. 26 is not, I repeat, not old. You have plenty of time to turn things around.
You may have to return to your home country for a while at some stage, in order to get some perspective. (also University costs would be cheaper there, no?)
I’d say after the Bolivia trip reassess. As long as you have enough money to survive. Finances really do control a lot of our decisions in life.
I’ve lived overseas for up to 15 years, and you reach a point where you can’t be totally happy anywhere. So don’t expect it. Life is often a compromise and happiness is what you make it. Learn to see the positives in any country you live, would be my advice.