I was never really one of the popular JWs who had a lot of friends , but being a JW for 40 years our family had built up many acquaintances - almost all of which fizzled out when we left. My wife was much more of a socialite but when she stopped going to the meetings , she lost about 100 "friends" almost overnight on Facebook as the rumours started to circulate. You could almost see them "unfriending" her in real time.
We got a couple of emails and letters from former JW "friends" stating that "I enjoyed our friendship but as you'll understand now you no longer go to meetings we can no longer have a relationship blah blah" etc but basically most people just dump you without a word. The one JW I would still regard as a friend and have a beer with every month or so knows it isn't the truth but is just staying in for family reasons & is really marginal now.
Like some others on this thread have stated , eventually you do make new friends - better ones that aren't conditional and people that are much more aware of life & interested in what is going on around about them. Looking back , most of the friendships I thought I had as a JW were really superficial.