Nick reminds me of an adult man I used to know - I knew him and his parents & siblings. The guy was ... manipulative, but very clever. He had traits of a personality disorder. He lied, but got very very good at hiding it and manipulating people through it. He was abusive in his relationships, always starting out exactly like the woman thought she wanted, and he'd slowly tear her down. He was... narcissistic? Even his own mother saw through him. I felt very bad for his friends and lovers, all of whom he hurt over the years. He was never my "friend" - I just knew him through family since he was a teenager.
Emotionally abusive relationships are not constrained to people that are living with each other. It can be between co-workers, boss-employee, school mates, family members and "friends."
On the other hand, these are **children** we are talking about, and Nick has a lot of learning and growing to do, and I would not just ditch him unless things got worse - and continued. What I would do is try to help my son recognize what is going on and know in advance that he may need to walk away from this "friend" because no one needs emotional turmoil.
As for lying in general, it is so pervasive in middle school, I was astounded. My younger daughter had some differences growing up and did not lie, which is actually developmentally "abnormal" according to some specialists. She knew friends lied. She said it was a survival technique they had in school and became so second nature. It escalates it seems, around 11 years old, before it gets back under control a couple years later - at least from my observation of it.
Except in cases like that person I was describing at the beginning. For him, he just honed his skills to near perfection.