So even if you keep your own coins secure, there is still a danger of theft performed with violence. You have heard of people who were forced to give up their coins/keys under duress.
Does this mean that multisig is a must?
The idea of multisig is to have multiple keys to initiate a bitcoin transaction on the network. If you have a mutli sig address, you could give one private key that would be useless to the thief. A 2-3 multisig adress would solve that problem. The risk of multisig is that you have to trust that the other private keys will not be found by anyone. A thief would need at least two of the private keys.
Alternative: Memorize your private key