Friendship should not cost a penny.
It should be based on love, not bank accounts.
That being said...If it were cancer or a life-threatening illness I would probably offer different advice for you.
Do not feel obligated to give her money or post her need for money.
If she is a true friend, she will understand that mixing money with friendship is a lethal combination.
If she gets angry at you for not contributing, that will be a perfect indication her friendship is not authentic. Nor unconditional.