@StarsAndSky0
I think you're either that kind of person or you're not, OP.
If there's a secret I'd love to know what it is, I've always been a miserable so-and-so! 
I've been both, so it's not 'either/or'.
The secret? Know that you are in the moment, now, and you cannot be anywhere else. This moment, now. The past is gone, the future doesn't exist. Now is all that counts.
Set your criteria for happiness. Mine is 'no/not much physical pain' and 'a roof over my head'. It those are fulfilled, I'm happy. It's my baseline. Anything extra makes me even happier. A cup of tea, a message from someone I care about, a sunny day, a pattern of frost on a window... all extra happy things. My clothes make me incredibly happy. I rationalised my wardrobe so that every day I can dress in clothes that are comfortable and that I enjoy wearing. My bed is a place of incredible happiness, so many pillows, duvets, so much lovely fabric. And so on.
Banking. Bank every happy moment. Notice, and tell yourself 'That's one in the bank!' No-one can ever take that happy moment experience away from you. You had it, experienced it, it's yours. It's in your bank account of happy times.
Try it. If I can be happy, anyone can!