I think Catholics believe the funeral is about purifying the soul for presentation to God. Like an offering. If the soul didn't live in according to Catholicism's dogma then it can't be purified. Sad but that's life.

@rainmanjr The catholic church doctrine prohibits providing any sacrements to those that have died in mortal sin. Suicide is considered a mortal sin so bad that they offically prohibit allowing the funeral service to be held in the church, or the body to be buried in a catholic cemetary. Local Bishops may grant exceptions.

I have had to officiate at catholic funerals because the local priest would not do it or the family was afraid of a similar diatribe from the priest.