By the sounds of things, she doesn't seem to hold you in the same (high) regard, as you do for her. Quite a few things stand out from what you've posted:
You've been together less than a year.
You already have hefty arguments.
She feels comfortable enough to make demands for a holiday as small as mothers day. Maybe this is just a difference in culture, perhaps it's a larger holiday in the US, but over here, mothers and fathers day is just a way of showing your appreciation for the job your parents have done bringing you up. It's not on par with say, christmas, or a birthday and unless the child is still very young, it's rarely conveyed by the other parent.
/shrugs
I wouldn't think of spending the rest of my life with a woman I wasn't already 101% sure about. Like DH said, life's simply too short. There's no middle-ground, either they're perfect for you, or they're not. Don't expect a change in personality from the other person, because it's clear that this is much less a personality issue, than an issue of how she views you.
Again... less than 1 year together. Nuts.
I've been with my girlfriend for nearly 3 years now and that's a heavy 3 years too, we've near enough lived together since the beginning. We never get to the stage where we're having arguments, certainly not big arguments. It sounds like you and your partner have far too many issues to consider getting married, especially when you've been together such a short time.
Summary:
UOD wrote:Posting on an internet forum is basically your way of dealing with what is going on in your gut...you know it's wrong to be treated this way but you want some backup.
<snip>Drop her like a bad habit.