Forgiven yes, I can say that any person with a mental desize can be a christian, my sister is mentally retarded but she knows her faith very baisc but all that is needed.
Suicide, that cannot be said what happens, its up to God. I have asked many times, and there is NO place in the bible that says that suicide sends you straight to hell. Its audiaphorah (that is spelled wrong) but it means it never says in the bible so we just dont know. Such as unborn babies, we just dont know. The common christian opinion on suicide is that if it is commited in a moment of weakness (such as a sickness) that your faith will pull you through, but that question CANNOT be awnserd on earth, by anyone.
If a massmurder repents and comes to christ (or better said Christ comes to HIM being that christianity is not choice related, thats a differnt reliegon) he will go to heaven, there is NO degree of sins, if you steal a candy bar, you are the same in Gods eyes as if you killed 2000 people.
Checked all that over in the bible before I posted, its all right. Ok.