No, not all cryptos are dependent on Bitcoin. Most of the coins are independent. What you see and feel is mostly a byproduct of panic sell. But if you are looking for safe and long term investment, I recommend you stick on the well-established altcoins and has been around in the business for several years already to be less affected by the price of Bitcoin. Very good examples are ETH, LTC, XRP, ADA - my portfolio is packed with these coins. I am also keeping a fair amount of Stakenet's XSN in my bag. An underrated hidden gem which I believe will going to pump real big in the coming months.