Fuck I can't tell you how realistic this question is right now. I lent a friend multiple times and now she owes me more than $1k and there's no sign of when that's coming back.
Yes and no, there's always stuff you learn and gain from a relationship so never fully regrettable but my main high school relationship it was just not a good time and only really fell into it because it was there rather than really wanting to be with that person.