Dog Bites

Question
I have a shih tzu, Benji, who is 5 years old.  I have had him since he was a puppy.  Tonight, he was on my mothers bed and I went to kiss him goodnight when he attacked me.  He left two gashes on my face, on about a half inch from my eye and the other on my nose.  My mother wants to put him down, but I'm not sure that after 5 years that is the way to go.  I should mention that we got a kitten about 7 months ago, but Benji and Jack have always been sweet, and they've never fought.  We believe they truly enjoy eachothers company and really are buddies.

Mom lost her job about 3 weeks ago and has been home every day since.  I believe that Benji sensed my mother's stress as we are in financial trouble.  He has become very possessive towards her since shes been home and hasn't been eating as much.  He even turns his nose up to his goodboy treats that he's always been excited for after going outside.  

After he bit, he did get hit.  My mother was furious.  He really knows that he messed up and has tried very hard to make up with me.  He's been licking and showing his belly.  I don't know if I could ever trust him again, what should I do?!

Answer
Using physical aggression toward a dog DOES NOT WORK and can, and often does, worsen aggression.  Is it possible that your mother has been interacting with this dog in such a manner without your knowledge?  is it possible she has used physical violence against him?  Don't discount this possibility; your dog is suddenly demonstrating active aggression which is NOT normal.  Aggression increases slowly; it goes from growl to snarl to snap, NEVER to full bite as you portray.  Something has occurred that you may not be aware of.  I don't mean to in any way disparage your mother, but your dog's sudden escalation in aggression is hugely abnormal.  Additionally, his sudden possessiveness toward her is not normal and might very well indicate that he is frantically trying to obtain her acceptance, which suggests she has strongly demonstrated to him that he is not accepted.  Also, the fact that she is so quick to say the dog should die for his behavior suggests to me that there is much more to this picture than you know.  You mention the dog is not accepting treats.  This can be a sign of two things:  huge stress and insecurity (dogs will not eat or accept treats when under enormous stress and confusion) or physical illness.  Obviously a checkup at the veterinarian is called for but my FIRST REACTION to this is that your dog is being abused when you are not watching and is having a normal reaction.  Something needs to be done and FAST.  This aggression will worsen if the situation isn't rectified and it will cost your dog his life.  If you feel your mother is behaving inappropriately toward the dog, get him out of your home.