Originally Posted by cymric
I think Jon will have several reasons for breaking his oath and coming off the wall.
1. Jon will defeat the others this has been foreshadowed in the fact that he carries a Valaryian Blade, The Others Fear him somehow and his younger brother (Bran) is most likely to become the most powerful magic user in the seven kingdoms.
2. Times are changing and as seen by Jon's friend (the fat kid) the Nights wacth is becoming more a standing army.
3. Jon has yet to find out about his families demise.
4. Robb Legitamized Jon making him the rightful Heir of Winterfell.
5. Sure his love intrest was cut short but love is like a drug once you have it and feel it you want more Jon will fall in love again, My guess is that it will be Daenerys or some other independent woman.
6. The scene were Bran crosses the wall shows us that the oath is spiritual not physical and henceforth the oath could be like that of the early knights Templar... They could Marry and hold their titles but their first duty was to the Order.
I don't think that Jon will ever give up his oath to the Night's Watch. Yes, times have changed, and yes, the Night's Watch is not what it once was. However, the return of the Others demonstrates the reason for guarding the Wall all those years. Before, they faded away and were thought to be obsolete. I think this final battle will prove the necessity of keeping the Wall manned, no matter how safe it is thought to be. Who's to say they won't return again?