Don't let this define you. Accept that your feelings and you are different things and that this will pass. It might not feel like it OP, but it will.

You're looking for sense pleasures to feel good, drugs and sex being the two listed, and then escapism to avoid feeling bad; sleeping.

Start doing the things you love again and really putting your heart into it. Whatever you can muster at that time. I know that you might not feel like it, but do it any way. Get out and go to class, see your friends, live your life. Don't rely on motivation and "feeling like it" because you have admitted here you have no motivation to do those things (I can't bring myself to).

So it comes down to discipline. If you're invited somewhere, go. If you feel lonely, organize something. If you have class, go to it. And you might not feel like you want to be there, but ignore that and flip it around. Pay close attention to the present moment and don't allow yourself to get lost in your head.

Are you being the best person you can be? If the answer is no (and I think the answer is no if you aren't going to class and participating in the things you like), then be that person, regardless of whether you feel like you want to.

Maybe there is something deeper to why you feel this way, but like I said at the start, don't let it define you. It will pass. You aren't a depressed person. You aren't a sad person. You aren't an empty person. These are feelings, there is a reason you feel this way, and you can work on not feeling this way. Don't label yourself and then make assumptions based on these labels. You simple feel this way at this present moment in time, and believe that you will feel differently at some point in the future.