What I have observed in last 3 months is that someone actually does not want it to slide below $200 mark. Just once 3 months ago it reached $160. Since then the prices are always varying in between $210 to $260 mark. It goes down for an average 15-20$ and then remains there for about a week and then again rises for about $15-20
Welcome to market, buddy. That "someone" is an aggregate demand for bitcoins from buyers. When Bitcoin reached 160$, that
might actually be someone selling a lot of bitcoins (followed by panic sells). As you suspected, it didn't last for long...