Work Problem - How Do I Handle This?

I have worked for my current employer for about 15 years. I like my job, and what I do, although the people are sometimes more than I can handle. I am not a big fan of "office politics".

My company recently began testing a new software, and my department was encouraged to learn the software so we could "train others". My self and another co-worker began to do this, my other two co-workers did not. It was not an expectation, a suggestion by a mid-management person. My co-worker, who also began working with this software, is part of a branch that really embraced the new software. Although I have worked at company longer, I continue to "travel" to different branches for different parts of my job instead of remaining in one location. I like this, primarily because not being at any one branch leaves me out of much of the "office politics" I wish to avoid, however it also has its disadvantages. The primary one being that my "coworker" who is tied to one branch, is considered the "expert" in this software and is being contacted to hold informal training sessions with other branches, even though I am at all of these branches and also know this software to a similar level that she does. She is more confident (and in my mind "out there") selling herself as an "expert" even though she is only working with this software for a few months more than I have.

I recognize that office politics are what they are, and since this person is willing to go to everyone and tell how knowledgeable she is, she is the one who is asked to hold these informal training sessions. She is also being asked to be involved in other meetings to determine whether we will transfer our company to this new software or continue on the way we were before, and so is one of my other co-workers who never even bothered to learn the software until late. He is however a "good old boy" and because of that was included in the meetings too.

My mid-management colleague who suggested us learning things in the first place and I met to discuss my exclusion from these meetings, etc. because I felt like I am more knowledgable because of the multiple branches I work with (and not just one) and she agreed I need to be more actively involved in this process - BUT, it was talk only. She approached a higher-up, who agreed, but since the committee members were already decided by individual branches I was not able to be included. She also said I was smarter than most, and that I could take my exclusion from the meeting (and the lack of information from my co-workers) as a threat - they know I am just as knowledgeable and don't like that. I don't really know what to believe, except words are only words. Anyone that really felt strongly would have backed up those words with actions - like involving me in the committees, meetings, etc.

I am started to get very frustrated by this situation, as my co-worker walks around with a more and more swelled head. She often communicates with me, and lets me know "how involved" she is in everything. They are not necessary pieces of information to share - it is primarily sharing in which "she lets me know that she knows something I don't know, although she isn't going to tell me what that something is". It is very childish, and totally within her character. She likes to be in the know and important.

Anyway, my question is - how do I best deal with this situation? I do feel like I know a lot, and that my co-worker is deliberately excluding me and wants me to know how "in demand" she is. I am trying to take the high road, but it is hard. The more I hear about her being "asked" things, the more irritating it gets that other people don't see me in the same why. How do I handle this so I am not so frustrated and stressed anymore?