Does how you feel about being single change?

I'm M37 and I generally like being single, alone, and independent and always have but I can also overthink/over analyze my life and then start worrying. Some days I'm okay and other days I get stuck in worry about what life may be like in the future as single and no kids. It's mainly about being lonely which does occur to me occasionally since I don't have friends where I live (my friends are in a different city), though thankfully I have family.

I start to desperately try to find posts, YouTube videos, etc of people older than me saying they love being single with no kids and have no regrets but once I come across a sad/negative video or post, especially one that negatively judges single people who don't care to date and don't mind staying single for life, I start worrying again.

I know the solution is to focus on hobbies and stop overthinking and stop caring what others think. I guess there's a part of me that wonders if anyone else is like this too. Is anyone else okay and confident about your life some days and then worried the next?