Some girls are naturally quite active on social media even in relationships but i'm not really sure if it increases after, largely because I don't really use it anymore. It doesn't really fit in with my cold-hearted vibe to have a cheesy facebook page...
I remember with my ex she went out straight away even though she'd still try to call me at like 2am and one of my friends didn't know and showed me a pic of her at a bar a couple of days later and she looked fine. She would have made a fine actor though. Haven't got a clue if she was upset, for how long, or if she still is, I very much doubt it, she definitely matched my coldness. I don't see it as winning really, she could have shagged one hundred guys that night but it doesn't make a difference, relationships are not a game, I no longer take an interest in your business and have no desire to compete with you, my feelings are my own and I will not let you play with them.