I think we've all been there! A lot of people go through this.
What I've learned is basically just getting out and about and staying healthy is best to keep yourself motivated and happy. Eat healthily, do 30 mins exercise every day, and just leave the house/go for walks/join clubs/get away from it all somehow if you're ever feeling unmotivated. Stay in touch with friends, family etc. and keep seeing people as well. Overall you'll feel way more motivated when you do sit down to work than just sitting down for yet another day of the same old stuff on your computer.
On top of that, you just gotta stick to it. Do the tiniest thing, draw a picture, make a single event, something like that at least once a day. You'll be getting somewhere, even if slowly.