I’m in my mid 30s and slightly introverted too. You know what, Jessie, you’re much better than I am. I have no friends – not even having a common best friend like your brother and you do. So I feel happy for you, honestly.
It’s natural to want a best friend. Yet at the same time, one needs to identify the conditions needed to meet and keep a best friend.
I’m glad to know you believe yourself to be a truly caring person. It’s one of those important conditions needed to meet and keep a best friend.
This is just a personal opinion – even though no one is doing the same for you, it’s ok. Why? Cos the care you give to others is genuine, so you would generally feel happy upon seeing others benefit from your care.
I think you would feel much better and develop a different outlook about your concerns of finding a best friend and meeting people who share things in common when you slowly start to think to yourself that, ‘hey, I’m happy to see that others are happy to receive my genuine care and concern. Should they do the same for me without me asking for it, that would be great. If not, I would be happy just by seeing that they’re happy’.
There is no one guaranteed way to get closer to what you want. But what you have is already with you.