"You've changed". "You're not as fun as you used to be". "Since you started hanging out with that person you're so different." All things that I've had said to me in the past and all things that have been said with negative implications.
I am a completely different person to the person I was a year ago. Just as I'm a completely different person to who I was three years ago, four years ago and ten years ago. I'm a very adaptable person and I am massively influenced by my experiences, my surroundings and the people that I surround myself with. I absorb other people's mannerisms and moods. I indulge myself in my friend's interests and often take them on as my own. I don't think any of this is a bad thing.