every time my sister and i talk about someone who is gay my mum says they are just confused they arent really gay which really pisses me off cause when i told her i was gay she wouldnt believe me and then she always realates being gay with getting aids so what can i do
That's a tough situation. But it seems like there are two main issues. Your mum views sexuality as a phase, and doesn't seem to be well versed on the aids issue. With the phase, this is possibly something that will change with time (and change the more you involve her in your sexuality). For example, by talking to her frequently about it - making comments such as "oh hes cute", or by introducing her to a boyfriend, this helps her understand that it isn't some "confused phase" that you are going through. Of course, you are the prime person who can change her view. Maybe ask her about people who spend their entire lives with a partner of the same sex - are they also confused for their entire life? As for her view on AIDs - perhaps doing some research on it yourself, so that you can correct her when she makes a remark. A good resource is here. If that doesn't work, or she doesn't believe you, printing out the resource, or finding a pamphlet might work better.
the thing is she knows alot about aids she was on the advisery council when aids first became an issue in australia
Well, it might if she is in denial... Or also, possibly (bearing in mind that HIV/AIDS was initially viewed as the "Gay disease") if she hasn't bothered to keep abreast of developments - or is just letting inherent prejudice override logic. One thing for sure - the more you can do to make her realise that it is not a "choice", and certainly not something you can change, the more she is going to having to rethink her position. I would guess that for most mothers, no matter how deep the denial, maternal instinct will eventually overcome prejudice.