How do I cope when everyone leans on me and no one holds me?

You can lead and care for your troops through anything, and you are the one they all lean on, while no one is holding you up. That is one of the loneliest positions there is. You have made yourself so reliable that everyone forgot you might need holding too. Strength that never gets to rest is not sustainable. Even the person everyone counts on has a limit, and pretending otherwise does not make you stronger. It just means you break quietly and alone. Needing support is not a failure of leadership. It is a fact of being human under load. Find someone who can hold you, on purpose. A peer at your level, a mentor, a counselor, someone who does not need you to be the strong one. Tell them the truth about how heavy it is. You spend yourself keeping others standing. Let one person help keep you standing too. You are worth the same care you give.