2 yr old shih tzu spoiling carpet

Question
I have a 2 year old shih tzu female.  She was always very good with doing her business on her pads that are always provided for her.  She was praised a lot as a puppy and was trained within 2 days.  Then i slowed down the praising and treats.  After about a year, she started to pee and poop anywhere she pleased.  Then she started peeing RIGHT NEXT TO HER PAD.  (She has a box so she can step into it.) At first i thought she didn't like the location of the bin, so i moved it to where she kept relieving herself.  But now I realized that she does it when she is left at home.  I cannot be with her 24 hrs a day.  I usually leave her in my room.  And i thought maybe she wanted to roam around the whole apartment, so I let her out when I'm gone.  I think I have done everything in my power and knowledge. but nothing seems to be working.  I tried ignoring the behavior so she won't correlate it to negative attention, praising her profusely when she goes on her pad, leaving out extra pads, and giving her more attention when she is good.  I'm not sure what else i could possibly do.  PLEASE HELP!!!!!

Answer
Restrict her to an uncarpeted SMALL area with her box while you are gone until she remembers what she is supposed to do.
Also, just in case have her vetted for a UTI. Sometimes they do cause bizarre symptoms.
I think restricting her to a smaller area will work very quickly. She just needs some reaffirming. You might also want to try a larger box. She may feel as if she's getting dirty if she thinks it's too small.
Good luck
Cindi