It's important to be clear: other people's experiences & "truths" don't trump yours. If their feelings & experiences are valid, then so are yours. That's where relationship maintenance comes in.
You have to be honest with yourself & with them when they are violating your boundaries or ignoring your needs.
Whatever they are going through doesn't mean they get to do that to you, even if you wish you could be simply the most supportive person in the world. Don't harm yourself in the process.