As said, if you do it take some kind of thing to defend yourself with, when i did it i was really down and just wanted to get away from where i was, so i started walking and it took 7 hours to get the first lift..all 3km of it! Got taken to a pub where they said i could get water, so i did (YAY!). Started walking and about 1km into that i got a 1km lift. Kept walking and it took another 10 or so km to get the final lift which i had finally decided i was gunna end up at a friends house, though i knew she'd left to go to a city that morning (was with her when left). Her mother was really kind, said could have a sleep and gave me food and drink lol. Thats my story, when i reached that house i felt mentally awesome, like i'd achieved something. Oh, and they let me stay for dinner, delicious!
Set a goal where you want to get, and GO FOR IT. Meet heaps of interesting people, take a small self defence weapon thing, and when you reach that place you will probably feel great! (Least till you realise you have to get back somehow lol)