Edit: I did never promise her to take her with me, I told her "we'll see tomorrow" and decided to drive off when it became clear that she would be late.
My (29, F) friend (32, F) and her parents were visiting me for some days and staying at my house. We're both hobby musiscians, she's a singer-songwriter and I love to sing classical music. A friend who is a professional singer helped me to get a spot in the signing class of a rather renowned teacher and I pay quite a lot per 45min lesson.
On the second days of my friends visit, I had my singing lesson in the morning, so I told them that I would be away for about 1,5 hours while they would be having breakfast. My friends mom suggested that my friend could join my singing lesson. My friend was very enthusiastic about it because lately she had been really inspired by classical music in her work. She wanted to get some advice by my teacher because she can't afford lessons regularly. I was hesitant at first, and my friend immediately started to take out her tablet and show me all the things she would like to get advice on. I told her that she could come and listen and ask questions about her work in the last couple of minutes of my lesson. But I could already see that her amount of questions would take up much more space.
I really like my friend, I've known her for years, but she can sometimes be very pushy and has problems stepping back when it's not her moment. It happened in the past that she was supposed to sing one song or speak for 5 minutes, but turned the situation in an hour long entertainment. So I was sure she would take more than a couple of minutes of my lesson. But since I pay a lot and I go there to work on very specific goals, I would love to get the maximum out of my lessons.
On the day I had my lesson, my friend as planning to just get up, have a coffee, brush her teeth and the come with me. When it was 15mins before we were supposed to leave and she hadn't gotten up yet, I decided to just drive off and let her know via text that I had to leave early.
She and her parents both called me TA for not being enthusiastic about taking her with me and driving off early. When I explained my reasons to them, they got even more upset, calling me TA for being so fixated on my own goals and on the cost of the lesson.
AITA for wanting to have my singing lesson for myself?