I know I've only got a couple of posts according to our spiffy new post counter, but I've followed this message board for awhile now.
I know that I can always count on everyone to be honest, rather than telling me what I want to hear.
I did get another email back from her, accepting my apology and saying she was sorry as well, that she had a bad day yesterday and was reacting to me the way she did because of it. She then said it might not be a bad idea for her to meet some new people so she'll think about happy hour.
In hindsight, I probably should have just declined my co-workers. It's been a hard year with re-locating and not having many new friends, so I am trying to jump on any social opportunities that I can, and I think I went about it the wrong way. My intent truly was to include her in something I thought she'd enjoy.
In any case, we've worked it out. I usually have the patience for dealing with her, but it's been wearing thing.
Thanks everyone, I appreciate your time.