I could have written your post so I understand how you feel OP and think you have been very brave. A lot of people will try to make you feel bad for feeling this way.
I too was brought up in an all girl household and too have all boy DCs - I have experienced some very dark times accepting that I'll never have a daughter and too seem to be surrounded by little girls and feel insanely jealous! You are not alone.
I encountered real fertility struggles too and while I was desperate for a baby I didn't realise quite how much I'd wanted girl babies until I gave birth to our final IVF son.
At my lowest with these struggles, I will honestly admit that I would not have judged someone for feeling the way you do - everybody's story is different and one person's struggle is not everybody else's problem.
Regardless of these issues, it doesn't matter whether you struggled or not in my opinion - every one is entitled to wishes and desires and gender disappointment is a real issue so you shouldn't feel guilty or ashamed OP.
The best advice I received while going through counselling for PND with my last baby was to face it head on - write down all of the things I really wanted a daughter for and spend an afternoon privately indulging the fantasy of a daughter, looking at clothes online etc etc. Really try to accept it and lose the shame surrounding it. It is a valid disappointment.
Once I accepted it, I felt much better and have felt much more positive since but I don't think it'll ever fully leave me.
Also thinking of examples of all the different children in my life and how they all differ in personality, regardless of gender helps.
It helps with the negative 'boys will be boys' comments when my children are actually all pretty easy going and very sweet natured, despite what people assume.
Some of the girls in my life have the worst behaviour and actively rebel against what their mothers want them to wear or do, while my boys will happily put on whatever I get for them and find the fun in most things.
I struggled in terms of not being able to buy much pink or floral stuff that I always found so pretty. The help combat this, I looked for clothes that weren't typically 'boy' with dinasaurs and blue - I went for more neutral and animal themed stuff. It really helped and I enjoyed it in the end too
Be kind to yourself, HTH 