I believe, correct me if I am wrong, is that part of the issue being taken with assisted suicide is that it might all be well and good for the person in question, a mantra I do not ascribe to myself but I am not about to impose on others, is it has ongoing ramifications for those who are still alive thereafter. A person could reasonably do it themselves without the assistance, this we are all aware of, but the aid makes the process easier; having somewhere there with you even if not friend or relative makes dying less painful to some extent. It makes the choice less difficult and the looming threat of failure, as well as presumed punishment, ostracization, belittlement, reprimand, whatever, a factor that is non-existent. It lowers the inherent thresholds of opposition that the mind should regularly be using to push back with - it makes death a more simple alternative than it already is. Yet suicide is not just about the individual in question taking their own life under their own volition, though it is entirely a valid argument that it is not always voluntary due to psychological compromise and duress, but the other people who are alive after.
Some of us have experienced the violent deaths and or suicides in person, which is to say that is obviously more traumatic than finding someone dead beside their bed with a bottle of pills or in the hypothetical case, a doctor's office where they were effectively euthanized. People by and large do not deal with death well, meaning that the person surrendering their life and voiding it could well do it against the consent of others who now become responsible for everything, be it the funeral, to debt, to children or spouses, to their pets, et cetera. The assisted suicide might be easier, given this is a clinical procedure and action, but the overall implications would be absolutely mired in a spiderweb of legal actions that others would willingly need to undertake for the to-be-departed member in question. The majority of people would not agree to this as they often care or even love other people enough to not want to lose them, but also because they do not want to assume more responsibility.
To step back for a moment and ponder upon it, let us say such a system existed where you did not need to gain the agreement of those people to do so. Again, the member undertaking the assisted suicide process is forcing their decision upon others unwillingly; unless they consented to dealing with the events after, as in accepted the risk and responsibility, the action that is already selfish still is... just slightly less so. Let us continue in another hypothetical where one could choose to allow the clinic performing the procedure to assume the responsibility, but at what cost? Those vulnerable to suicide are already compromised, meaning they might well surrender that which is not theirs to or worse for them, be unable to afford any of it or offer such a legal transfer of authority. No less, is it not somewhat morally questionable at all tiers that in this example, people trade quite a bit of what they own to die outright when they themselves are not in the right state of mind?
There are greater issues with this proposal than I believe are being admitted and I have not so much as sunk my teeth into them here as my point is more about the people left behind, which is where I think greater issue is taken. For myself, I do not disagree with allowing people to commit suicide - there is only so much you can do to prevent them from choosing the final option - but at the same time I will not condone or encourage the behavior, let alone as a practice which will only reasonably still harm others in the process despite it being "nicer" to look at or think about. That shiny veneer is an illusion, a distraction.
To summarize your points and give a WTL;DR: you appear to be saying that suicide is harder for those left behind than it is for the people who end up dead. I agree with this. It's literally the #1 argument I can think of to get someone to NOT commit suicide.
BTW if any of you out there suffer from depression and were prescribed Abilify, feel free to never ever see that psychiatrist/physician again. Stuff does not work for "mood stabilization" and is meant more for dementia patients than as a behavior drug. Psychiatrists, psychologists, and behavioral therapists seem to mostly be money-grubbing w....erm, harlots.