Wow, you sound like me - although sometimes I only have a few mouthfuls and feel quite sick. I finally worked out that this occurs every single time I have wine and have forgotten to drink much water during the day! Not a nice feeling and embarrassing at times.
If my water intake has been good, it takes me a whole glass to feel tipsy and probably 3 before I'm feeling sick. It's good and bad - it's cheap because I can't drink much in 1 sitting but there are times when I wish I could sit back with friends and enjoy a couple of wines without getting blotto!
I weigh approx 89kg at present and have always been this way with wine, even when I was 52kg (my smallest). The funny thing is that all the females on my mum's side are affected exactly the same way by alcohol. When I was younger, I used to sit back and laugh at my mum, grandma and aunties because they'd have a glass of wine and would all be a giggling mess! Now the same thing happens to me.
Do you know the strange thing is that I can basically have 5-6 drinks of. say scotch and coke, before feeling the slightest bit tipsy! Weird!
Oh yeah, and my mother in law is allergic to alcohol! I remember that she was violently ill for 3 whole days when she had a quarter of small glass of wine! She just has to have a sip of any alcohol now and she throws up for a couple of days afterwards. Obviously, she doesn't drink now and hasn't touched the stuff for at least 15 years, but before that, she used to enjoy a few drinks and feel fine. Dr's have done tests and can't explain why she's allergic to it now.