I watch my girlfriends dog every once in a while and she just isnt getting potty training.  She is a little over 5 months old and some weeks she does a great job and the next week she'll go to the bathroom everywhere but outside.
I do understand that part too.  I actually got a puppy a couple months before her so I went through this all.  I just wish her puppy listened as well as mine because he took a couple months as has been doing great since.  I know it'll click eventually...I just wish shed hurry up :)