Hi Cherry,

This is just my take from what you have told us. Whenever a person quits smoking, you can be sure they will have withdrawal symptoms from the nicotine, I know because I quit about 12 years ago. (Should take about 2 weeks for nicotine to clear outa person's system). And even after nicotine is out of system you have physchological issues to deal with in smoking, such as just the oral and hand fixation of holding the cigarette and the puffing of it, when you take that away, you crave it, and it can drive you crazy for a time.
And because of your Mom's age, may I ask has she gone through menopause? if not yet, she may be starting and most women as you may know go through lots of physical and mood changes at this time of life, which can make them cranky sometimes and moody. There are natural and synthetic hormones women can take for the change of life or menopause. Your Mom should see her doctor if she hasn't about this and he or she can guide her as to the best way to handle her menopause systems if that is what she is going through.
Hope this helps...