Take the time to explain your boundaries clearly to your friend. However, if they continue to disrespect your needs, it might be time to reconsider the future of your relationship.
A simple way to evaluate the health of a friendship is to assess how you feel after hanging out with them. If you often feel tired and drained, that’s a red flag.
Talk to your friend about the amount of emotional support disparity between you. You can't be your best if you're surrounded by people who dampen your spirit and zap your energy.
Sometimes, people will require a little more support than other times, but if it's not generally an even split and you can’t depend on them, something is wrong.
If you notice you give more than you get, talk to your friend about the amount of emotional support they require from you, and set some boundaries to rebalance the friendship.
If your friend constantly needs you to the point that you feel more like a parent than a friend, that's a sign that you're doing the bulk of the emotional labor.
If you find that you are always the one who reaches out or has to make plans to hang out, that's a sign that you're doing most of the work in the relationship.
A simple way to handle this situation is to stop making plans with that friend and see how things progress. Meanwhile, start forging other friendships that make you happy.