I too have run into this issue lately. I suspect it is a recently updated mod, the key is finding it. Launching KSP and starting my game instantly pegs out at 97%
Edit: Well, for me at least - the culprit seems to be scatterer and the associated EVE / Stock Visual Enhancements. Now stable with under 50% usage of RAM. See if pulling those mods help. I'd be interested to see if it can be duplicated.
Just checked out the Scatterer thread
Looks like it is killing rigs left and right of memory. Culprit confirmed.
ItchyBrother's post in Modded memory leak/CTD was marked as the answer