What does it mean when someone asks you how did this change your socially

Answer 1

I guess you were a shy type of person who used to not mingle with anyone or not attend any outing like parties or any type of functions, and than suddenly people might have started noticing your change of behaviour, mixing up with the crowd, having outings, going for parties, that might be the reason someone told you how come you have changed your social behaviour.

Answer 2

How did this change YOU socially?

How a certain interaction or new information may have changed the way you interact socially with others. Eg: the Internet has changed people's social behavior with the way it is so easy to share information, people will post pictures of their dinner as if everyone else needed this information or in the way that some can be quite more aggressive than normal due to the absence of any physical retaliation.