You havnt said a single thing wich is pertinent to the individual wishing to end their own lives - Being pressured into something is not Euathenasia.
Euthanasia - "a deliberate intervention undertaken with the express intention of ending a life, to relieve intractable suffering"
All the word refers to is the act of assisting suicide of a person who is suffering severely enough, the reason doesn't come into it.
What if their expressed intention is not of their own choosing? That's the point I was trying to make, imagine a family with say a critically ill or severely brain damaged member older member, grandparent perhaps, has to be looked after by everyone and can not function alone yet is capable of discerning whether or not they want to die but not able to act on it, they look at the family who are clearly not enjoying have to look after them and think maybe they would be better of without them, is that a just cause for them to want assisted suicide?
Clearly it isn't, they could be relocated to a care home or given an aid or any other possibility to give the family less responsibility for their care, making them both happier.
How about if instead of this person simply not wanting to be a strain on the family, the family actually tells this person they would be better off dead and they can't be bothered caring for them, they give them a choice of assisted suicide or neglect.
Would you let either of these people go in for an assisted death knowing it's not what they actually want? I doubt it, the problem being there is no way of knowing if these people convince themselves its what they have to do.
These are reasons why it should never be a simply option, too many variables and outside influences that can cause people to think in ways they normally couldn't, be it depression or as above, thinking of their family or any number of others.
As Bledd said, it should be dealt with on a case by case basis.