Exactly what Reborn said above. I came back in twice. The first time I really did believe that the JW's had the truth because I had never studied anything else. I couldn't comprehend how anyone couldn't believe that JW's had the right religion. Therefore I just figured that most everyone that got disfellowshipped still believed that JW's were correct, either that or they were possessed by demons.
When I had my first judicial meeting, I went to the elders and told them my sin and set up a time to talk with them. I said I was sorry because I really was and I broke down and cried with remorse. The meeting took forever and still they couldn't come to a conclusion, so I went home at midnight and made an appointment for two nights later for more torture. When I went back, they discussed matters with me for 2 more hours and had me wait outside the room again, then they called me back in and told me that they had decided to disfellowship me.
It tore my world apart, it was all I'd known all my life. Why would the elders disfellowship me, I did what I was supposed to do. I didn't have to come to them with my sin, but my conscience hurt so bad that I felt I needed to so I could set things right with Jehovah. I thought a mistake must have been made so I appealed the matter. The 3 meanest elders from the circuit were called in to call me names and berate me and call me a prostitute against god and tell me that maybe they could forgive me eventually if I chose to come back, but Jehovah might not be able. And that was that.
I decided to go out of my way to do my best to come back in as fast as I could. I had plenty of friends that were JW's back then and I had a girlfriend who said she would wait for me (although none of them, including my gf would speak to me while I was df'd). Anyway, I tried hard to get back in, I came to all the meetings and I studied every night. After only 6 months I was reinstated and everyone was so happy. People lined up to shake my hand and hug me and they cried. I came home that night and called my girlfriend that said she'd wait and she said things had changed, she'd tried to wait but she'd found a great ministerial brother who was a up and comer and they got married very soon after I was reinstated.
During my disfellowshipping, some of my friends started to have doubts and fall away because of the way that my disfellowshipping was handled by the elders. They didn't feel comfortable in the congregation anymore and didn't feel that they could talk to the elders about anything for fear that it would turn on them. Like an idiot I decided to exclude these friends from my life, but not before one of them told me about the Watchtowers past and let me borrow a book called Crisis of Conscience.
Things don't happen instantly, and it was the same for me. It took me a few years to come around to finally reading the book and a few years after that to figure out that I really didn't believe the JW religion at all. During this time of spiritual unrest within my mind I got disfellowshipped again and pulled another sister out as well, whom I ended up marrying.
After 3 years out we decided to come back because we wanted to have more contact with our parents and siblings. So ahe spent 1 year and got reinstated and I spent another 2 years trying to come back in, I had to go through the original elders that disfellowshipped me even though I was in another congregation, so it took awhile. The people in the congregationg weren't very loving, I got a "hi there" and maybe 2 hand shakes but that was it.
After that, my wife and I just slowly faded away. We haven't been to a meeting since last year's DC which was amazingly boring. Basically, I owe thanks to the elders that disfellowshipped me the first time, because otherwise I'd probably be a ministerial servant married to a pioneer trying to scrape by without the college education I'm glad I got while disfellowshipped.