I can't go through with it

A phrase that, once uttered, will inform others that you, being the one who said "I can't go through with it", are unable to complete the task at hand. But there are multiple feelings connected with the phrase. The user of the phrase may actually go through with it, but is just complaining about doing it. Also the opposite may be true, that the user may be simply unable to do it. Deciding if the person is just complaining or really can't do it can be hard to tell, your best bet is to make them do it by any means possible.