Choice only goes as far as not infringing on the choices and lives of others. Regardless of the fact that a certain issue BLATANTLY violates this rule, suicide is not that issue.
This being said, suicide is not a right, not a choice someone has.
It's not in fact, acceptable to commit suicide. I don't think society does enough to stress that suicide is not a choice or an answer.
You know, there was a time in my earlier teenage years where I was at suicides doorstep. I had done something that at the time had seemed unacceptable to me, and I was overwhelmed with guilt. It definitely was NOT the "it's selfish" argument that saved me from that fate, and the "it's okay" would've been about as good as saying "DO IT! I don't care."
The thing that saved me, was that deep down, I wanted to live. Suicide was tempting, but I wanted an answer, something to make it not so tempting. A combination of my friends continued presence and support gave me the time I needed to give suicide a nice, long thought. Eventually I found religion and that gave me a solid answer, that a forced afterlife would be worse than any life I could manage.
That solid reason killed suicide for me. I never went back to that place again, and developed better social skills as a direct result. I think the "It's okay"/Do it/Do not care stance could have made the entire ordeal a lot harder.
It could have even gotten me killed. The lack of support might haven denied me the time and sanity to think things out.
As someone who has been there I'd like to say that what I WANTED was to not want to commit suicide anymore.
He's right, actually. Now someone who has been in that place is telling you. If anything, I think you should ask him to explain rather than insulting him by denying him his right of speech. Just saying.