Can't Feel The Things I Once Did

I recently found that when people feel sad or depressed, they can usually look back in their mind for memories that made them feel good and happy. They like to relive those to feel that joy again, at least to some extent.

But what happens with me is that in times of sadness it feels like a gigantic blanket of melancholia engulfs me and I can't look outside. Even if I try to think about the times I did feel joy and happiness, it just doesn't work. When I recall such instances, I can remember that I felt good at that time but its not something that I can feel again, it just becomes information.

When I try to relive these memories in my head it feels like the gloom that I feel in my present leaks through the gateways of my mind and floods into these once happy memories and when I rewind them in my head it essentially feels like sitting in a 'meh' mood in a beautiful place full of magical flowers, dreamy skylines. And no matter how deep I look into my mind, the melancholia stays.