I hate feeling like that and I do feel like that quite a bit. Sometimes if I am in a REALLY negative head space I find myself (you know that little voice in your head?) saying things in my head that take me way back to being 14 again "I should just shutup and not say anything" "no one is listening anyway" etc, etc...
I detest people talking over the top of me, I will just withdraw and not participate in further conversation if that happens.
Another thing that really bugs me is when for eg:

You go to a friends birthday/ party/ celebration what have you...the same people are always invited, you have met them all in the same surroundings at least 4-5 x over the last 3 years, but every time you see them they make like they have no idea who you are. HATE IT!!
My dp says it is because I am just good with faces/names etc.. but I'm not really, I just don't see how hard it is to say," sorry I dont remember your name, but yes, I remember you from last time"

I have just recently unfriended a heap of "used to be close" friends from FB. One girl, I always went out of my way to drop in and see her if I was down her way, she would whinge about not seeing me etc.. it started with "I was gonna ask you to be my bridesmaid but you were in Darwin so I asked my other friend" (I have NEVER been a bridesmaid, she knew how much that meant to me) then I didnt get an invite to her baby shower (it was all her MIL's fault she said) then she was posting updates on FB about how she was only 10 mins away from where I live (like every weekend) but never once dropped in to see me, I withdrew, then eventually just deleted her. feels good! LOL

I do try not to take things so personally, I am a lazy friend most of the time, so I understand how life gets n the way a lot of the time. but if you make the effort with me, I will mostly return that effort 3 fold.

In regards to birthdays and things like that, I tend to be the one making the effort when it is mine, no one else will and the way I see it is that its my birthday, my celebration, I will shout it from the rooftops as I love birthdays!

I'm sorry you guys feel the same way sometimes, I know how awful it can be.