Sorry to hear about your father. But his death doesn't need to have a bad effect on you and your mother. This may sound odd, but the severity and the duration of the effects of his death are so much today only because your mother (and others in the family) have probably allowed it to affect her.
It will be a challenge to persuade your mother to consult a Psychiatrist
. You may have to find out the reason. She may be worried the doctor will put her on medicines for life. But you can try giving her the option of psychotherapy
. Psychotherapy ("Talk therapy") can really help her understand why she gets upset so easily. Underneath every 'sustained' emotional disturbance lies a thought which is irrational. If she can explore her irrational thoughts, she will be able to modify them into rational ones.
I suppose the option of psychotherapy can be offered to her. I hope she chooses to go for it.
Abhijeet Deshmukh, MD