she cries around morning or at noon, she said no one understand her, and she wants all her children, including my father to be on a good terms with each other. My father is the oldest of the three and they aren't in a good terms, and my grandma is more caring to my father than to my aunts so they got jealous and like to badmouth my father. One of my aunt is living with me to take care my grandma, she is not patient to my grandma.
Who is treating grandma's depression? Is the doctor aware of these crying episodes? Is it possible that they are triggered by low blood sugar? Is grandma diagnosed with dementia or cognitive decline?
Very often, in situations where one child is the caregiver, the other children become the "golden" children who can do no wrong. This can be extremely irritating to the caregiving child. Also, in some families, male children are treated much better, no matter what they do.
Are you and your aunt being compensated for your caregiving? Are you both getting regular respite?
More information about this situation will get you better advice from us.
Ask your father for his advice. Does he think these crying fits are a way of commanding attention? Does he remember any similar crying fits from his mother when he and his siblings were still children? There could have been bouts of depression that went unnoticed when the family was much younger. This would be a case for asking your mother's doctor for mild tranquillisers, not heavy anti-drepressants. Sipralexa is often prescribed for this. It can be taken long term without side effects.
To make life in your home easier, persuade your father to write his mom one letter to her to say that everything is fine between the siblings and that "nobody is quarrelling ". A letter would do the trick better than a phone call, because the letter is a one-way communication. Photocopy it several times first before you give it to her, because your grandma might enjoy tearing it up!!
Talk to your aunts, particularly the one who lives with you. Tell them that kindness to their mom is free and would make your own life a whole lot easier. Ask them to not gossip or sound off about the family to her. Instead they should bore her stiff with talking about the weather or TV soaps. They could share with her some of the thousands of funny cute animals videos on YouTube to make her laugh.
If grandma carries on with her hysterics, this is either deliberate attention-getting, in which case you scold her and tell her to stop at once. Or she enjoys a good cry, so give her the hankies and weepy DVDs to watch, and leave her alone in the room without an audience.
Good luck!!