I had to read through your comment a couple of times. From the sound of it, you’re likely in a better position than many other people here, and what worries you isn’t the lack of social contact but the depth and quality of it.
This is a common issue that a lot or even most people face as they get older. I think that a lot of us have been able to fill this gap by finding significant others and starting families. I wonder if the trend towards settling down at later ages and holding off on having a child - or forgoing it altogether - is also part of the issue.
Social media doesn’t help, but the answer to that is to stop using it, or, at the very least, to keep yourself from using platforms that encourage comparisons.