One of my kid's trainers was like that--low energy, seldom smiled, never volunteered a bit of information, though did answer questions. She was positive in lessons and didn't yell or anything like that. For a while we just accepted her for what she was--not a people's person. Everything was fine. Only after changing barns we realized how emotionally draining that trainer was. It is difficult to be with a person who struggles to communicate.
I read some of Stacy's blog some years ago, and I was also turned off by her grammatical errors and poor spelling. Not a big deal, really, but she doesn't seem to be a skilled communicator. And that's okay. There are plenty of trainers who are selling their brand more effectively, for better or for worse. There's choice.
I agree that the OP shouldn't have expected personal attention or to be friends with Stacy, but empathize with the OP.