I need some moral support!

You could join the Long Hair Community forum, they are very committed to keeping length there, you may find it inspiring.
Personally, i think if you want it shorter get it cut, it will grow back. Hair should be fun, you should have it however it makes you happy

Thank you... I love long hair (enough so that I've only gotten the tiniest of trims in the last four or five years), but sometimes I see short haircuts and they're JUST SO CUTE! :'(

Have you ever had it short? I think everyone should try it at least once in their lives. Many long-haired people find it really liberating to just chop it all off.
Short hair will be much easier to wash and dye, but you will have to style it more, no just bunging it into a ponytail when you can't be bothered lol
You could plan a series of styles that go from short to long again which could be fun
If you want to stay long but are bored, consider adding layers or a finge or changing up the colour of course

A few years back it was cut just below my jawline and heavily layered for maximum floofiness. It was a lot of fun, but long hair is a lot fun too. The main drawback is that I don't want to bleach it, since growing out the bleached part would be... Very difficult. Kind of limits my color options.

Bleach it now, and then cut the bleach off when you go short?
You can dye the bleached area back to your natural colour if you get sick of being bright.
Thats the great thing about hair, nothing is permanent

I'm definitely not the person for the job! I've rarely had my hair longer than shoulder length and mostly just under chin length or short!