social life
In order to survive, we had to get good at being happy alone. And then I think we got too good at it. What a mind f&$k, if I do say so myself. Now I find myself actively behaving more like a shut-in. Are you? Here are some signs.
Extreme extroverts will have more social-media related fights than is normal for couples today. Neither of you is great at self-editing on social media, and may post things that the other believes provoke flirtatious comments from others, or were just too private.