I think you're falling into a trap of semantics when you're talking to people here. Your original point I entirely agree with, and I don't think it's really refutable... But only in the context you define it in. You can say that you're not separate from anyone else or anything at all, and all is one, and that's irrefutably true... In that context.

However language and human concepts don't work that way. Meaning doesn't work that way. It can be fundamentally true, but in any practical context basically meaningless and impractical.

I do think your original point is a good perspective to have, but I also think it's important to understand and communicate the perspective it's from. And I don't think you're doing a great job of that, frankly.