"The donetsk and luhansk "republics" are puppet states sp... i don't think we can assume that their secessionism is genuine... even if a large number of the population favoured joining russia it's very doubtful that would still be true after the invasion... "
Indeed, also to the comment about Crimea. All these areas had some "pro-Russian" sympathies (whatever that actually means) but were in no way looking to break away from Ukraine. The planning we now know for this started in Russia some years before. Thousands of pro-ukrainians were attacked and fled after mounting peaceful pro-Ukraine protests against what was happening. In many cases the demos were brutally attacked by kremlin-backed thugs.
There's an interesting report here on life in the occupied territories of Ukraine here. The idea that there would be a "UN monitored referendum here" is massively insulting to these people and their families, and to the tens of thousands who have fled.
https://www.bbc.co.uk/news/world-europe-63076570