I appreciate you asking us this question. At 18 you have been with him for a significant portion of your life so it makes sense that you would feel this so deeply. But this is more than trying to figure out if he wants to be with you. This is a time for you to reappraise whether or not this is the right relationship for you to be in.
I would never push this. I would not try to make something happen. The essence of a good relationship is to be able to celebrate each other and share your mutual vulnerabilities. Neither of these things are happening with the two of you now.
I would grieve this loss. Grieving is not easy but is an essential part of life. And while it may seem overwhelming at the moment — giving yourself a chance to heal from this may help you see that you deserve to be in a relationship with somebody that is in as much love with you as you are with them.
I would give this some time for you to heal. But I would also rely heavily on your friends now to help you through this and give yourself a chance to let them help you recover and find some new interests.