Depression. And how to deal with it.

Hi, my sister is suffering from depression from her childhood and recent only diagnosed that she is under depression from her behaviour. Her mind is not stable she keeps on thinking something and always it end up in negative thinking she has undergone some childhood incident which make her feel restless everytime. She has one major issue about marriage she don't want to do marriage but her family torching her to do she is totally against marriage she says she don't have interest in marriage life nor in sex life. She says she don't have feeling toward any boys and she feel something towards girls. She totally hate men and something she feels like she should have been a boy not a girl and ya her behaviour is also not like a girl she seems to be like tom boy... need your suggestion what should I do I have to show to her doctor but what is this mean all about can anyone pls explain me what does it mean and how to deal with it.