I think everyone even once had that period of time (some of us long-term, some short-term ones) when you just lose your heart and nothing brings joy, you just live day-to-day life. In the morning you wake up cause you have to, all day long you are thinking about tomorrow, you don’t cherish THE MOMENT, honestly because there is nothing to cherish at that time (or at least you think that way), at night you go to sleep with a though that you have to get up tomorrow.
As for me, I have those periods from time to time but likely i figure out when they came and how to fight with them, and trust me, you HAVE to fight with them.
First reason is a routine. Yes, I’m talking about daily routine I stuck in. Those days usually have very basic timetable: getting up (when I don’t want to), breakfast, university (with all their crap classes that doesn’t carry any beneficial knowledge), dinner, couple of episodes of my favorite TV show.
Now when I think of more dissent reasons I cannot think of any. Yes, mood, weather, relationships may influence but they are not the major factors.
THE SOLUTION. I think that you probably can guess how to deal with it. SPICE UP YOUR LIFE. Fortunately this time my university helped me deal with this period. Since I’m graduating this year, the essential part of eduction is part-time internship. 8 weeks.
When I started working, I met new people, my timetable got changed, even my habits changed and my behavior.
So I’m not saying that the changes should be radical, no, you can do it step by step, just keep on looking, may be try to find a new hobby (btw I did that as well – I pretended to be a grandma and learnt how to knit).