Is it normal to just stop talking to your friends mom

My best friends mom really likes me as a person, and she's always really nice to me and we get along well. And periodicaly we would converse on line or by texting. Just a simple hello or how are you. But one day out of the blue my friend just told me to not talk to her on line or by text. I was really surprized at this so I asked her why because we've never had any problems and I never got an answer from my friend. She never pushed the issue so i didn't push the issue so once and awhile we would makes small talk in that same way. My friend very in an angry way with no explanation told me to stop again. This time i insisted to her i did not undersand what the problem was and i wanted to know why i should not. My friend said i shouldnt need a reason from her and that her saying no should be good enough... We got into a huge argument and we are now no longer talking to each other. Was it wrong that talked to her mom even tho i had no real reason to stop?