So sorry people have been so rotten to you about this. People should know that when it comes to our children they don't get to speak cruel words about them. They don't get to be judgmental.
When my son-in-law died of suicide I ran into all sorts of people who seemed to think that they were being supportive when they ranted about how selfish they thought people who took (or tried to take) their own lives were. I dearly loved my son-in-law, who was bipolar. He was a very good man and the last thing he was is "selfish." Quite the contrary. His deep caring for others often lead him into unbearable depression.
But even if he WERE selfish, saying so would be the least comforting thing for me to hear, along with all those dumb platitudes about being in a "better place," yada yada.
Whether the loved one is still with you or has passed, it is NOT the time for anyone to be critical of that person. Instead of speaking, one must listen with empathy. Let the grieving one tell YOU what they are feeling, and accept sometimes the feelings maybe contradictory,, but this is not the same to argue or contradict. Just listen.
Say, "I am so sorry you have to go through this right now."
Say, " I think about you and your daughtr/son often."
Say, "I can't imagine how much pain you must be feeling right now."
Say, "I am so sorry you are hurting so much."
Say, "I wish I could take this pain off your shoulders, but I know I can't. Just know that I will listen if you want to talk."
And then listen. Don't argue. Don't add your own two cents or even a ha'penny. Keep your mouth shut. Nod. Use a soothing voice with..."I know...I know..." Hug and hold if the person is ok with that. But don't push it.
Just BE WITH that person. Period.
It seems way too many folks have never learned how to listen.
Best wishes for better days to come...