Moving past reputation?

Throughout summer I’ve been on a personal journey to improve myself, socially. I went on vacation for 3 weeks and found vast improvements when I was alone for a bit and had time to reflect a little. Then I came back home and landed in an internship where I felt even closer to my desired traits. Fast forward to now, I started hanging out with my friends again.

Overall, I feel like I latched onto a lot of immature social traits throughout the years. Jealousy, the struggle to be inclusive, and insecurities. Heading into senior year of high school, I feel as if I should move past these childish tactics and move onto being more mature in these aspects.

I notice that I’ve been doing great with new groups of people, specifically older individuals. I feel immensely connected to my team in my internship and like an organized individual. Everything changes when I enter an environment that includes people from my past (the times when I wasn’t so great). It’s like the people from my past bring out all the bad social habits I’ve been working on, even if they themselves aren’t relatively bad.

I want to start acting a little more collected in familiar environments, not just places where I have no past associated to me. I just feel like it’s hard to become something new when having a different reputation attached. It’s like I subconsciously adhere to what people expect of me.

Has anyone else done a 180 with their personality and moved to a better place? I’ve heard of scenarios where people go ghost mode and socially disappear for months, but I just don’t think my friends deserve something like that.

TLDR; subconsciously abiding to my iffy reputation in old environments and having a hard time growing as a person