I feel jealous now and thats highly unusual.
I don't know why I get this picture of your girl being awesome because I'm usually such a cynical prick. I guess I believe you.
Anyway, you just need to learn to relax, forget about everything you've been taught and just be for a while. Just be with her, not all the voices in your head and her.
You don't have to be any more used to this than a baby needs to be of breathing, it will happen naturally if you only let it. I'm starting to sound like a broken record...
There is no past to ruin the present apart from what you commemorate and don't you worry about the future either because we create it through who we are. Worrying is half the loss because while you do it, it affects your words and actions. And those little doses of negativism over time grows to affect your life to become less and once you get to what was once "your future", you will have made all your worries a reality and you go like; "See!? I fucking knew it! This is just my luck!".
So stay positive and meet obstacles as an oppertunity to grow stronger with providing solutions. Nothing will end badly unless you make the two of you those typical sour asses who are the reasons things turn to shit in the first place.
Love isn't blinding, it should just be a natural part of life but we've made life a heap of unnaturally blinding bullshit. I mean we have even made pain beautiful so we can be pain junkies. What the fuck is that shit?
...So anyway, what is actually natural no longer fits in that pile of crap, that's what makes love so misleading to us. Together with parenthood, you know how that is supposed to be so hard but it really isn't. And sex, thats an entire fucking science by now but the less you know the better it gets, but now we are just afraid of all the wrongs we can make while we strive for that idea of perfection which is just a heap of oppinions about this and that.
Don't induldge in it, don't even fucking care, don't listen, don't look. Turn your eyes away from all the bullshit this world heaps over your heads you don't need any of it, it will only make your lives a burden.