Why do I feel uninterested in my beloved interests?

It's definitely not because I feel like I need to mature or anything. Adults love video games and anime as well. I view them as visual arts and I even listen to the soundtracks. But lately..I've been feeling a little uninterested. The last game I purchased was on Black Friday and my excitement lasted until 2 weeks later(still playing through, though). I'm not feeling that excited feeling that I should always feel. This feeling started at the end of summer. I keep remembering the good and exciting memories of the games I've played and the anime I've watched. Can anyone help me understand what is up? Only 2 of my friends watch anime(one moved out of the country) and 1 friend plays video games(but she is not that close to me.)