Oh aye, I did feel with Jiraiya unfortunately. Ironically Kakashi didn't care for Rin (probs gay or asexual/aromantic or just too traumatised to want/have a relationship I guess) but she did pine hard for Kakashi too. There was that constant theme of friend zoning and cucking as you said. Fucking sucks, especially when it keeps happening IRL and you see it happen to characters you like too.