I personally believe that when an illness has taken that much control over someone, forcefeeding is acceptable.
I am sure that if the person genuinely wanted to kill themselves, they would have found different ways. As previously mentioned, malnurishment can impact thoughts and I personally believe that that makes the person a danger to themselves. I'm sure there's an act that goes towards when a person is unable to make a correct decision and puts themselves or others at harm they can be detained, and it is rightly being enforced to help out those struggling with eating disorders.
I can understand why it can be argued that it is against human rights and such, but when you're really putting yourself at that much risk how can people just stand by and watch?
The laws are in place for a reason - and I completely agree that forcefeeding someone who cannot feed themselves is the right thing to do.