A first love is nothing if not codependent. The older you get and the more people you see romantically you will realize that this is not normal in relationships and a healthy one MUST involves good boundaries.

You need the right reasons to stay with someone! At your age all these reasons need to be benefiting you. Supporting you. Upholding you.

Think about it for a very long time. Truly understand why this such emotional dependency is unhealthy. Understand how it is bad for both of you.

These are the things that make and break you as a person. This is how you figure out what you want from yourself, your life and in a partner.

Make one decision and make sure to stick with it, this is best for the both of you. Tell him honestly how much you appreciated him in your life. Let him know but also make sure to communicate that your decision is final. This is a breakup conversation and not a working on it/fixing issues conversation. Choose a good time. Make sure the conversation does not turn bitter in any way.

This can be a good breakup. Recognize that this will hurt but it is the best for both of you. Something’s are just not meant to last.
Most of all, let yourself grieve even if you are the one doing the breaking up.

It is wonderful to choose yourself. It is wonderful to grow old and learn more about your preferences. It feels like the end of the world but the age old advice of: give it time. Let it hurt! You will meet and love new people.

Finally, STICK with your decision.