How to not feel bothered?

I don’t even have something major to be sad about like grieving death or immediate danger.

I try to do stuff like hang out with a buddy during the day.

One thing I feel bad about is that the woman I’m dating randomly seemed distant recently and in my own flaw I pulled away for the time being because I didn’t want to risk getting more hurt trying to filter things.

I try to feel better by thinking there’s so many men that don’t know her so they don’t feel sadness over her, why should I be bogged down? Or I think I can find someone else is she is not compatible instead of feeling sad over her

There’s just so many people with much bigger problems and they seem to function find and laugh and socialize, how can I not get distracted by sadness?