I would also never leave mine outside unattended. I gave in..well not really me..my fiancee did... and now they sleep with us in the bed. Not so much Timmy but Mimi was a whiner and she still is. Whines for anything just like a kid and her daddy doesn't make it any better...sometimes I look at her and tell her "Do you know your a dog" lol because she acts just like a spoiled rotten little girl and now that she has LP forget it...its gotten worse.
It will take some time. I know how frustrating it can be...I have 2 and they are only 1 month apart. I went through several sleepless nights but it was all well worth it.