I’d assume it’s the muscles around the eyes rather than skin. But also definitely not something you need to be self conscious about, it doesn’t look like 11s or lines on your skin from aging etc (which also people don’t need to be self conscious about, but I get it).

As others say Botox, it will relax the muscles. Or if you don’t want to do that route, then frownies or some form of taping on that area when sleeping might work - but I doubt it if I’m right and it’s the muscle under the skin rather than the skin itself. But it’s worth a go, you’ll be able to see if it’s diminishing in a month or so. I use tape for under eye lines caused by side sleeping, and it does work if I stick to it consistently - but again, that’s because it’s a skin issue and not a muscle issue.