I think you did fantastic! I’m proud of you for being assertive and not aggressive with this person. That shows real strength of character. Something that’s helped me to be assertive has been “The Assertiveness Workbook”. I started realizing in life that I was constantly being walked over, pushed around, and in the end BLAMED for everything that other people did to me! I had had enough! I quickly began reading everything I could about why this was happening and it turns out I had a very passive nature or personality. So I set about changing that.
Now, I take regular opportunities to stand up for myself, being assertive, and to feel good about doing so.

Something I found really interesting is that when you start being assertive not everyone will like you for it. Pushy personalities want you to remain a push over - because it gives them what they want. So you will get some kick back for sure. It’s a battle of wills for awhile. But just keep being assertive and you will get to the point where people either exit your life (great! You don’t need those people anyways) or they respect you way more!

Let me know if you want to chat more about this. It’s been a scary but wonderful journey for me and I’d be happy to share some tips and tricks with you.

All the best )