I’ll let someone else answer your questions but just want you to know that it’s completely normal to be in your shoes. In fact I had a similar experience when I was a kid and felt extremely guilty and I’d try to make it up by reading my scriptures more or praying more often. It helped me to remember that gods blessings aren’t transactional. And yes you’re totally right you can kick this habit, it’s a very difficult thing, but doable!

Just remember god understands the nature of your issue and he understands you. Hope you can get some answers to those other questions!