Hey, I haven't really read what other people have said, but I've felt the same way. And I think that motivation is not something that really comes from outside means. You can have a go at yourself and force yourself to do something, but that isn't helpful either, because you will eventually resent yourself! If you say "oh I'm just lazy" you will believe you're lazy and it makes things worse. (Speaking from experience there.)
My opinion is that if things feel like they don't matter, maybe they really don't matter to you. Like money, status, all those shallow things, they are really not good motivators. They motivate in a negative way, out of greed and fear and judgement of others and yourself. It's not healthy and a lot of the time it just feels worthless anyway.
I think the only real motivation that is worthwhile is love. What do you just *love* doing? Use that to motivate you. I know that might be hard if you don't know what you love doing but there is a whole internet of info out there. Find something you love. And use it to get you through the day. Like right now, one thing that is keeping me going is the idea of a holiday on a sunny beach and swimming in the sea. I love the sea and I haven't been for years! I haven't booked this holiday but I tell myself that I will have one soon if I am good and get my studies done. So it works.
I also love helping people, and I know that I can help people better by helping myself. Motivation isn't necessarily this thing where you get all fired up and have to do something - it can be just an idea or a hope or a wish. I'm being a bit poetic here but I hope I make sense. Good luck!