@LANDALE I too was active in the Mormon organisation for 30 years, I don't know what you mean by "3 year stint". I very much wish it had been a 3 year stint. If I had put as much energy, time and creativity into my career as I did "building up the kingdom of heaven on Earth" I'd be a wealthy woman. Let alone the 30 years of tithing!
Anyway, I saw early returning missionaries shunned both in the UK and USA. I can hardly tell you the details of the young men who killed themselves, but I knew them and/or their families.
When I spoke in sacrament meetings about loving my "wayward" son, how I loved him as much as any of my children, his worth as just him made him precious to me, I would always be approached by tearful people who would tell me I was the first person to say that. That they had a son or daughter who had left the Mormons and the parents had been judged and condemned themselves. It was excruciatingly painful for them. Often their leaders had told them to cast out that child.
LDS certainly do believe in inheriting their own planets and always have done. I was taught it in LDS lessons, lesson manuals and broadcasts for 30 years. I really don't know why you think they don't believe it or ever taught it.
I think when you say LDS broke away from Mormons you are referring to the Re-organised LDS. Who broke away from who is a good question, both groups believe they are the original, with "priesthood authority" passed down from Joseph Smith. The original falling out was over who had that "authority".