Obsessing about my babies sex, even in my sleep

I have 3 sons and I found it very hard finding out at my anatomy scan that DS3 was a boy. Lots of people seem to find their GD goes at the birth, mine didn't. I love my baby boy and always have but it took me a long time to bond with him and even now I resent him for not being the girl he was supposed to be.
Jump forward nearly 4 years and I am almost 19 weeks pregnant after swaying heavily for 8 months to even get pregnant and a IVF/PGD before that which failed.
I have no bond with this baby yet, I have only told very few people and I hate anyone talking about it including my husband. But at the same time I am completely obsessed with wanting to know that it is a girl so I can go shopping and enjoy my pregnancy, at the same time I really don't want to hear boy and have all my hopes crushed. I also really don't want to find out in front of my husband because he will be nice and supportive and make it even worse.
I live in NZ so elective US is not an option and hubby really wants to come to the anatomy scan( which will be my only official chance to find out unless there is something wrong with the baby).
Last night I had a bizarre dream that they scanned my baby and were telling me it had fluid on the brain and brain damage and I was still shouting at them that I needed to know if it was a girl or boy because that is all that matters and they told me to come back on Sunday at 8pm.
I have access to, but no training on, an ultrasound machine so I have even tried scanning myself to try see. I can't see a penis but in all honesty it is way harder than it looks and I am probably looking at the babies toes.

So what now? Do I go for my scan and find out and risk 20 weeks of being sad/ angry about another boy or all the fun of knowing its a girl? Or don't find out so the dream can stay alive a bit longer?

I did US on myself both times too, if you keep practicing you'll probably be able to see what it is, use online pictures as a comparison, and if you can post a pic here, others can help guess :D
What you can do is ask the ultrasound tech at your scan to kindly hide the gender from you at the scan, but to write it down and put it in an envelope for you to take away - you could even ask for two, one for you and one for DH. That way you can find out in private, take a drive to somewhere nice and just be ready. Baby is well and truly there and part of you and your family, whatever sex it is. I hope you can accept it for what it is, not what it isn't if that is the case :)
Good luck xxx

Thanks, that's good advice. I managed to work it out with DS2 but only later in the pregnancy, and I think finding a penis is easier than not finding one.
DH is just so nice and sweet and supportive. Which drives me nuts when I want to be upset and angry. He will do whatever I say, whether we find out or not. He won't understand the envelope thing, he thinks, if you want to know then just find out. If you don't, don't. He doesn't get that I don't want him there when I find out because he just wants to be supportive.
I know it's all my issue which is why it is so frustrating.

That is such a hard decision. I found out with DD3 and I was crushed, but it was right for me.

If I get prego again I HAVE to know asap. Either way I'll decide what to do from there. If its a girl, NO ONE will know but my GD friends and DH. If its a boy I'll get to do whatever I want!!

You may ask Hobbermittens for some advice. She swayed for her DS and didn't find out until birth. She was killing us the whole 9months because she wouldn't find out but we love her so we tried to be supportive.
She said finding out she was having DD2 at 20 weeks ruined it for her so she wouldn't do it again and went team green.

Good luck honey, such a tough spot to be in.