[fho]

> But if your social network is just your colleagues,

I found this to be especially true in academia ... I spent about 10 years at the same university in different groups and have not kept many of the friends I made along the way.

This goes both ways, I spend a lot of that time in one group and got to see several "generations" of students and colleagues come an go ... After a while you just stop trying to have deep connections because most are there only temporarily.

(Also at some point students just become to young to befriend :-) )