what? i can understand that a bank asks some questions if you handle big sums of money or have unusually big transactions that you usually do not have, but this sounds bad. do you have to answer them? i would consider to look for another bank.
Yes. If you do not answer and show proof to everything they are asking for, they will put your money on hold for as long as their investigation is running. Funny thing is that I just came from a different bank. I signed up at the bank I am talking about because my previous bank told me to immediately stop using that bank account in combination with Bitcoin. But in general there is not much difference between banks as they are subject to the same laws.
Then you are pretty much screwed up
If you are heavily involved with Bitcoin, you may not be able to cash out your bitcoins and get fiat to make a living. People having thousands of bitcoins and living off them, might really consider the possibility of moving to other countries which are more loyal to Bitcoin in this respect. Though that would create a whole stack of other problems on its own like possible language and cultural barriers, citizenship questions and so on