Yeah, I opened a thread once about me wanting to explore non-monogamous possibilities with my husband (whom I am very happily married to, mind you), and it very quickly turned into a shit show, people were jumping in the bandwagon to judge me, telling me my marriage wasn't working, assuming things I didn't elaborate in the OP at all, and just generally attacking or wishing me ill.
I just stopped responding to the thread, worked out my shit with my husband (we both enjoyed the experiences and are doing fine in that department, thank you) and thankfully I had some really nice exchanged via PM, with people who were genuinely interested in helping and sharing their own similar experiences.
I also am very positive that most of the people who were attacking me on that thread did so out of personal insecurities. Usually people criticize in others what they hate the most in themselves. So yeah, this discussion is legit, but don't let it get to you, OP. I suggest looking for advice in one of the community threads, they are usually much more of safe, respectful spaces than the wilderness that is the off topic board.