This is the sort of issue that stays in the family circle and should never leave or be spread (even to closest friends).
So I ended up here. This is probably the safest place I can go and let my inner feelings be known without consequences.

My problem is my Aunt. And my grandfather.
I loved my grandfather very much. I always admired his attitudes, actions...everything. He was a noble man. His posturewas solid, sometimes cold and bitter. I never really understood why he looked so sad most of the times. But he kept being noble nevetheless his sadness.
My guess at the time (I'm 20, he died when I was 15) was that hewas sad because he was a widow for many, many years. My mother and aunt lost their mother when they were in their early twenties.Anyway, I never got to know my grandad very well, since he was very reserved about his thoughts. I remember asking him many times what he was thinking about, and he kept answering in a sad tone: "I'm thinking about my past".
This always saddened me. I guess every oldman thinks about the past and stuff, but the way he said it...the twinkle in his eyes...
Thing is...only after he died 5 years ago, was when I begun knowing him better, hearing my mum saying things about his life.
I learned that he was involved in threatre plays, that he loved music but never had the gift to learn it well...etc.
When I first heard of this I was fascinated. How I wished I could've known this when he was alive...we'd had much to talk about, since I love music and, on the contrary of my grandfather, I actually know how to play some musical isntruments. And I was involved in threatre too.
But I was young when he was alive. I didn't know him. He didn't open up much.
Then I found an old musical instrument in his countryhouse that belongs to our family. In my language the instrument is called "Bandolim" and when I found it the strings where rot and the wood was weak. My mother told me my grandfather bought it when he was in his mid-teens, but never really managed to learn the instrument. I immediately took it to a store, where it was clean, and the strings swaped into new ones.
Since I belong to my college band, I quickly learn the instrument and everytime I play it I remember my grandfather.

Then more serious stuff came in.
My aunt has a very serious psychological disease. I don't know it's technical name, it's some derivation of Esquizophreny.
While my mother married my father and formed a family, my Aunt lived alone with my grandad all his life since my grandmother died and my mother changed into a house with my dad.
Aparently, my mother only figured out my Aunt had this disease years after it started to show/develop, because my granddad tried to hide it.
For love, my grandad tried to hide my aunt's disease from everyone.

I have to create a new threat to tell the rest.

Have sex with your aunt

I'm not entirely sure what your problem is, can you clarify? It just sounds like you're venting about your life, which is fine, but I'd still like to know if you're asking anything in particular.

I'm wondering how you'd all deal with this issue. Would you avoid your aunt, or still be nice with her because although it's difficult for you, it's not her fault she's mentally ill.
Would you be moping around, or try to ignore it?

Because she keeps entering my bedroom saying random stuff, asking weird questions (typical of her disease); every 10 minutes. I dunno how to act around her. I can't really face her. Everytime I do, I imagine what my grandfather has gonne trough, and it pains me.