sorry for the loss mate i can feel you on 21st of sept i too lost 2500usd of bitcoin in poloniex exchage i think a remote session was on my computer that hacks everything.But my loss is way more bigger than yours .But my money was what i put in it .I mean that was all my hard earned money.
Your is bitcoin growth money ,but on the other had that is huge.Did you contacted the electrum support yet check if they can help any .
And also did you enabeld 2fa on your wallet i mean with that huge amount you must have enabled that.on that case your 2fa will be in your mobile .even there is key logger they cannot spent that without that 2fa.
next time please use 2fa on electrum it helps.