Yeah I can completely relate to this and have attributed it to being introverted as well. I am extremely social when I do attend social events, often being the most talkative if it's a group of 4 or less, but need to recharge alone the day after whereas my friends will continue to want be around each other. They often accuse me of being horrible at communication and making the effort to hang out with them, but to me, it's a simple matter of needing to be alone for a period of time, which I assume they are not familiar with as they all seem on the extrovert side of the spectrum. Sure, it's important for me to override that sense of wanting to be alone to catch up with friends and be a better communicator/friend, but it is in no way natural for me.