if your boss asked if you liked it - you should have said "i like this and that, i think the color is nice, I like how the caption came out, whatever".
To me, this is where the whole thing really went off the rails. (The situation, that is, not your post, cicero.) Why in the world did she feel compelled to ask the OP how she felt about this project? Making a map for a stranger's wedding, that was outside of her job duties? That's like asking someone how they feel about changing the toner cartridge in the printer, and then questioning their loyalty to the company that they're not completely over the moon about the experience. Based purely on the story as it was relayed, I think the boss was also tired from the long day and annoyed at the request, and was basically picking a fight. (I agree with the "transference" theory.) Completely inappropriate.
I've worked for non-profits for over a decade (all in the performing arts) and in my experience, this is the exact opposite way you want to treat a donor. For the reasons others have said, but also because it makes it nearly impossible for them to take you seriously. With theatre, this is a guaranteed way for donors to view your company as just "kids putting on a show".
OP, my advice would be to let it go (expect for the cell phone part; get your own). If she brings it up again, and pushes the matter, I would be direct. Let her know (politely) that since she's your boss, you'll do the tasks you're told, but you'd rather do Betty's tasks after the work tasks are completed. And if she brings up the perks again, I think it's fair to use blarg's wording and let her know it seems like she's trying to punish you. I honestly don't think you have to be concerned about being fired. If you're in a two-person department, I'm guessing you shoulder a lot of responsibility, and firing you would be a huge inconvenience for her.
And if you can stand a little more two-cent psycho-analyzing: I think she really WANTS to give you perks. She wants to feel like she's bestowing these gifts upon you. She wants to think of herself as the Generous Boss. Which is why I think she was also super worn out from the day, because she shot herself in the foot by calling in those favors, so to speak. You only get kudos for being Generous Boss if everyone else notices on their own; you can't call attention to it yourself. I've dealt with a "But I'm a Generous Boss!" or two in my time.