Forgive me, but it sounds to me like you're getting secondhand information from your mother, and it might not be entirely objective. She's telling you how people feel. And, based on how she herself feels, that may be designed to have an effect on you rather than just tell you how it is.
This might be a good opportunity to talk to your friends, find out what your mother has said to them, and maybe set the record straight if necessary. She obviously has a very subjective view of who you are, and how she feels about that may influence what she says to others. If she's given them an inaccurate view of who you are, and why you're living the way you want to live, then they only have that to go on, you know? Maybe you could sit down with them and have a discussion where you find out what they have been told, and then put your side of things across to them.
People who don't like you doing something can sometimes be... conservative with the truth, when it comes to trying to make you feel bad. She may be taking things said out of context, embellishing the emotional feelings behind them, and using them to have a very specific effect on you.