My mother also suffered from depression throughout her life. I was 12 when I first realised that there was something different, but didn't know what it was and so couldn't label it. It started when she refused to leave the house except occasionally in the evening when we would all go out in my father's car (their marriage had ended by then, but he lived in the coach house so was close by). She refused to seek help and instead was if the pull yourself together age and class.
I don't know how to explain the impact on my brother and I other than to say she stopped being our mother. My brother went on to be the one who could never do wrong, despite the fact that he developed a drug habit, bunked off school and failed all his exams. In him she saw herself and I'm pretty sure he was the only person she ever really loved.
Me she tried to control, but I went to university and met my husband and married young and lived away.
My brother stayed near to our parents and married someone like our mother and of whom she approved. She now controls and abuses him like our mother did, but he can't see it, won't leave and so we are estranged. He now battles alcoholism.
My husband was also abusive, but I left and recognised I was depressed and siought help. I was told frequently by my mother that I was weak and pathetic for doing this.
My mother continued to be depressed and as she got older she frequently talked about killjng herself. She was agoraphobic, alcoholic and despite all her talk about wanting to have a life and do something, never managed to do anything, go anywhere. She wanted to die, so when she started developing symptoms of a particularly nasty cancer she ignored them and, as much as possible, kept them from us. My brother visited her often, as did my father and they were worried and tried to get her to get help. Nothing worked. She was finally admitted to hospital with end stage cancer. She was pissed with us because we got to her before she died.