Science

The one nice thing about working in an office is making friends with coworkers and getting insights on their friend group. You could move somewhere new and the job is a good place to start with it. Now people work from home so that avenue is closed.

The next easiest way is thru your children. They make friends and you naturally become closer to their parents. Unless they are low-functioning autistic and can't make friends. All the parents in that class are exhausted from constant care of their child and your kid has 0 interest in hanging with theirs anyways.

Suddenly you are 40. All your friends from your 20s & 30s have scattered to the winds. You yourself have moved to MCOL state just to stop your rent from taking everything and the only ones looking to make friends are younger and have no interest in older people. You tried everything, going to events alone, joining clubs alone, inviting the people in your boxing class to concerts. Offering to pay for everything. But the constant failure just introverts you further. You stop trying and your hobbies are your friends now. Unfortunately not everything can be like the movies. Sometimes you just lose.

Hold on to your friends tightly everybody.