First off, you won’t be perfect, just like everyone else, your ideals will be hard to keep. Kaladin couldn’t say the 4th ideal for an entire year, despite knowing the words, just because the ideals are hard does not make you any less worthy to say them.
And you think your actions won’t matter, so what? If your actions don’t matter, then that means you can follow your ideals, not because they’ll help, but because you want to, because that’s who you want to be.
I know that it’ll be rough, and that my words may not do much, maybe it’ll help for a bit, but later the feelings will return. The important thing to remember is who you’re trying to be, and try to act in accordance with that. I can’t promise it’ll all go well, it most certainly will not at times, but you might as well try.
I know it may not seem like it, but you do make things better. It’s never fun to just sit by because you think you’ll make it worse. But if you have to keep restraining yourself, just don’t. Based on what you’ve said, you can’t make it worse by interfering
Its hard, but if maturity is restraining yourself from trying to help and change things, then don’t bother being mature, do what you think is the right thing, not what others are telling you is(Ironic I know).
I’m sorry you have to go through this, I hope something I’ve said has helped, but we’re here for you.