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I eventually stopped overextending myself and became more honest about what I could actually do.

That probably helped you see whether they valued you or simply valued what you were doing for them.

Yes. Their reaction told me a lot about the situation

Sometimes setting a limit reveals more than another hundred acts of sacrifice ever could

They initially thought I was becoming selfish, but I saw it differently.

People can call a boundary selfish when they're used to having unlimited access to your effort

I still wanted to help, but I wasn't willing to keep hurting myself to do it.