What are Russia's demands though?
Demands are evolving. Today Lavrov said that if and when negotiations start, they will have to take into account "realities on the ground". I gather that's a pretty transparent way of saying that we get whatever we control at that point.
Demilitarization, to me, is meaningless if Ukraine can be pumped full of weapons again the minute hostilities stop. Denazification is stupid, but I'm sure they will extract some language from the Ukrainians which can be shown to especially Nazi-obsessed compatriots of mine that the "mission was accomplished". It may mean disbanding the volunteer battalions that got integrated into the AFU, or them writing in some language into their constitution which rules out equivalencies between USSR and Third Reich. Again, to me it's a bunch of hot air. Territories is what this is all about.
Russia doesn't look like she's willing to start any peace negotiatons
Strange. In the news I read it's the opposite. Lavrov complaining that the Ukrainians decided to leave negotiations in Turkey after getting some "assurances" of support from Johnson and Biden. The negotiations had been at some promising point apparently (Russia wasn't doing too hot at that point either). Officially, the Ukrainians have been saying - "no negotiations after Bucha", first. Then they said, "no more negotiations with orcs after the theater bombing in Mariupol". Finally, they did come back, but with some list of negotiation points that Russia doesn't even want to look at. Some sh!t about returning to Feb. 24 lines, and discussing special status for Donbass (and more or less surrendering Crimea). Who are they joking? That train has left the station long ago.
But I am not sure if you're right about deliveries of weapons to Ukraine
Podolyak, the advisor to Zelensky that covers this direction, has been saying they need at least a 1,000 heavy caliber guns. The numbers so far are something like 10% of that. PzH 2000 or Caesar, it doesn't equal 10x or 20x of a normal 155mm gun. It shoots maybe 2-3 rounds a minute more, is a little more mobile, and has some armor from light weapons. It's not some Wunderwaffe.