Question: Trying to understand my family dynamics

My mother has a sister and a brother. My mother has many issues herself and I’ve witnessed rages over slight things, especially when I was younger. I suffer from anxiety and paranoia too. My dad is a transvestite and hid this until he dressed as the opposite sex and posed to the next-door neighbours, causing the police to visit our home. Why would he do this? It caused me and my mother great problem, having to move home, and I got depressed.
My mother doesn’t get on with people, lacks empathy, think she is usually in the right and others are always wrong. Can get into a rage, then becomes manipulative and reflects over her behaviour to you. She was supposedly diagnosed with OCD, although she has seen many physiatrists, not sure what was said. One apparently suggested that she leave my father.
My mother claims that her mother and the sister are partly to blame for the way she is. And I have never believed this before, but I am not sure now. For example, my uncle has very unhappy and became an alcoholic, coincidence? Then my mother was an alcoholic too when younger, but stopped. The sister is very different, she is extroverted. Growing up she had me and I was like a second child.
I think I saw a different side to her though for the first time, possibly confirming what my mother has said. Although I am not sure. I visit the sister every week and have done as an adult. Her and my uncle were always good to me – took me on holiday, etc. However, it felt like a personal attack on me when I last visited before leaving. In so many words it came across as “You need us more than we need you.” “You don’t have many friends”, etc. Christmas is coming and my cousin, who hasn’t ever been close to them is visiting, I now feel left out. They are basically wanting me to stay away over Christmas – very unlike them. I think it might be because my cousin is going with a girlfriend and he has said if I go he will not - There was a fall out when his dad died (the brother of my mom).
She seems to want to now be closer to my cousin, or maybe I’m being paranoid, but don’t think so. She keeps going on about his girlfriend, and the idea of him becoming a stay-at-home dad. The thing is, since we aren’t talking it is difficult to keep hearing about this.
There is so much more to discuss. But please advise. I feel like I cannot trust my family, not sure who to believe and what the right thing is to do.

Hi
Thanks for the reply. Do you mean my aunt? She actually has no children of her own and claims to love me. There is a lot of talk about wills and leaving money. I was supposed to be getting more than my cousin. But she seems to possibly want to make things more equal even though she hasn't had much to do with him and loads with me? Either way, as long as I'm in it and get half, I feel ok with that.
How should I approach it? It isn't easy to know what she is thinking or why she is reacting like this. It will be the first Christmas I haven't visited, but I said well in advance that i would stop at home this year because it is less stress between me and my mom.