@Alex hello (hope u can understand my english)
For me personally is a best friend someone where it feels the same even after not seeing each other for years. I personally have many different mask for the people that surround me like for each friend group or social environment but when iam with them I can let it slip not completely but Partially, I know they know iam a lost cause and we are both okay with it because if he ever faces a problem I would be there for him and he would be there for me even if we called each other 3am in the middle of the night. Iam sorry for your loss but someone that doesn’t listen to you isn’t someone you need to call your best friend and time and social environment changes people that’s a s*y truth we all need to accept.
Greetings from Germany and heads up
