Asking this sort of question is like asking whether gold can disappear. Well bitcoin will only disappear when gold disappears. This simply mean that it is going no where.
The only thing that will likely happen is its value dropping, alas! It will pick again. Now lets look at some reasons why bitcoin is here to stay.
Bitcoin is a Magic Dragon. It is a piece of code running on thousands of computers, and it is peer to peer networks and it is decentralized. You can not turn off a peer to peer system without stopping the other systems running on the same internet network. Bitcoin is going nowhere. Even if all the countries in the world starts regulating it, it will still exist and people will use it legally or illegally.
People are hooked to bitcoin because it is filling a certain need, apart from filling a physical need, it fills an intrinsic need. Anything that has such a need does not disappear. Lets look at an example. People go for religious service to gain salvation, even when such persons don't get it, you still see them committed to such service. So not matter what, people will keep buying, using and trading it continuously and therefore it would maintain its existence.
As you learn more about decentralized currencies, you will come to understand why bitcoin will not disappear. You are in the right place, at the right time. The Bitcoin community is intelligent, perhaps more intelligent than those in the traditional financial institutions, ready, and able, to continue to pioneer the existence of bitcoin.
The sign of bitcoin disappearing is hanged on altcoins gradually disappearing. But there is no sign of that happening. Instead they are growing by the day.
Ok. Lets cut this short and say the only thing that will make it disappear. It is if there is an invention of a very perfect new digital currency. Anyways, this will only make bitcoin price to be very low, that people will just keep it as souvenirs.
But come to think of it, if bitcoin really disappears especially quickly, without something else filling its vacuum, this will be disastrous, it might lead to the collapse of the entire financial system, because it is like a chain that is connected to the system.
In conclusion, bitcoin will only disappear, if the world seize to exist.
So guys what do you think, can bitcoin disappear?