If they do help themselves, they will be prosecuted.
However, I totally agree this should not be done by their own Doctor, but by a volunteer Doctor who agrees morally with the principle. Even better - the Swiss system where volunteers who have been trained in counselling and supporting in such situations, will call at the home and discuss their needs + ensure that there is no coercion or doubt or any kind.
When the volunteer is totally satisfied that this is the case, they will make an appointment to come back again in a few days time, and again interview the person on their own to ensure the above - and if it is clear and certain- will prepare the lethal drug dose, which will be switched on by the person, NOT the volunteer. All sorts of mechanical and electronic devices are available to ensure that even a severely handicapped person can do this. Some of the volunteers are doctors, most are not.