I completely understand where the OP is coming from. I went through exactly the same. Always despised anything stereotypically girly, never could relate to girly girls as a child, always yearned for and imagined having boys.
So I was secretly a bit disappointed when I found out I was due a girl. I told myself she wouldn't be girly though, as I wouldn't conform to the stereotype. No Disney princess or too much pink and a range of toys for both genders etc
Until 2 all babies are gender neutral so it was fine, at 2 she suddenly became obsessed with pointing out flowers and pink and anything stereotypically girly with glee! To my utter horror! At 6, she still adores pink, my little pony, barbie, she is obsessed with anything sparkly or glittery, if she could chose anything to wear it would be long floral dresses all the time. She wants to be a princess and live in a castle and can often be heard muttering about how she can't wait to get married to a prince and wear a pretty dress. Contrary to other posters saying you won't care, I DO. I do dislike how different she is to me as I find it hard to relate to her. It's taken me a long time to not fight her preferences. I now give her a choice of pink and princess-y quite often instead of only offering more unisex choices and it is working, and she is mellowing out. I do think its important to question them and continue to offer gender neutral choices.
Dd was the only girl who wore a spiderman costume on superhero day at school (all the other girls wore Disney princess dresses) She adores dinosaurs (even if she plays tea parties with her toy ones) she is obsessed with Pokemon which i encourage. Her favourite film is ghostbusters. She likes superhero stuff (I got her into it via powerpuff girls who are an excellent role model!). I read her some books thy challenge stereotypes like pippi long stocking an babbette cole books. When she asked for a pink bike I got her a dark pink one with black tyres and blue sparkles instead of the hideous candy pink and white with a dolly basket. You both might have to learn to compromise, not letting the pink completely take over and continuously offering lots o choices and not making assumptions of their preferences is key, but you also have to learn to let them make their own decisions and may have to accept a lot of things you hate!
I'm currently pregnant and declines finding out the sex this time. I'd still love a boy, I still hope if its a girl it's not as girly as dd, but I know once they are in my arms I won't care so didn't want the chance to find out and dwell and be disappointed. I don't like my dd's preferences, im often disappointed when she picks ugly dresses! but it doesn't mean i don't love her even if i don't want to join in all her games. She doesn't like my favourite things and would rather I was more girly and we both have taught each other a lot about differences. I find we always get the kids we least expect, almost like they are there to magnify are flaws and teach us a lesson!
My tips are fight it while you can, as a baby. By Scandinavian baby clothes (polarn, smafolk, h&m all great for none pink frilly girls clothes). Buy garages AND dolls (my dd ignored most of the typical boys stuff but not all). Question their stereotypical choices, but mostly-if they do love pink then give them lots of opportunity to choose it. If you respect their choices a lot of the time, they will be more suggestible to yours.