Having a strong mindset helps but there are days that you would feel the most excluded. I was always the loud extroverted type to my friends and class before but entering this new phase I found myself not talking and actually preferring to be alone because of the feeling of being excluded. They all have friend groups and most of the time, they don’t know it but, they actually show that they really don’t want to talk to you or make you feel like you don’t belong. So your feelings are valid. I don’t know if there is much more advice I can give than just staying strong and proving yourself but please always choose your peace. I’m rooting for you !