I’m not a bank!

So say you loaned your ex boyfriend some money. He was going through a hard time and needed help paying bills and did not really have any family he could count on. He gave you his word (in writing) that he would pay you back in three months. He started paying you back at first in small increments but still owes you $750. It’s been waaaay past three months and nothing but excuses. Do you write it off as lesson learned, beg or what? Its not like you have the money to lose! Ugh!