I have decided to reword my initial post. My basic question is: Are there any sins that Hashem will not forgive?
[PLEASE DO NOT RESPOND TO MY OLD POST BELOW]
WARNING!!!! THIS QUESTION (AND THE POTENTIAL ANSWERS) MAY CAUSE DISTRESS.
I understand that mainstream Judaism says that all sinners can do teshuva and will be forgiven their sins. [As per several responses below, please do not emphasize the following comment] The only exception is if one committed one or more of the three "cardinal sins" of idolatry, murder and deviant sexual behavior. My question is, are there any sources that suggest the exact opposite? Namely, that Hashem will not forgive one's sins (or certain sins) no matter what an individual does in terms of teshuva?Which sins are they if any?
I am thinking of this in the context of Tanya which, at least to my understanding, explores the issue of how a person would give up hope if they saw themselves as a rasha (evil person.) Are there other sources that suggest one will be condemned to gehanom no matter what they do but Hashem doesn't want us to know that because we'd be too depressed to learn of this. I'm kinda thinking of the way doctors years ago thought it better not to inform a patient of a terminal illness because they would lose hope.]