if your getting dragged out of character.. then you are letting them control you.

no one said being yourself was easy, but it gets easier and easier to ignore the 'bad vibes'. you ignore them because you want to be happy, you ignore them because you can do nothing for them and joining them is not a good option, it may be the easier option, it may be the option everyone you know uses.. but that doesn't mean it is the only option.

being still within yourself is something you cultivate, you do this on your own, by yourself, away from the negativity. it is a practice, and when you do it, when you get stronger in your own ability to stay still by yourself, then you can work on doing it in the real world.

as someone that has spent much time on this topic, i can say the only thing i've found that works is meditation for strengthening your stillness. becoming more connected to all that is so that you don't get disconnected by the bad vibe people.

good luck in your efforts.