I've updated Java to the latest version and re-downloaded the client.  Ran Malwarebytes, Avast, and CCleaner, and they're always active in the background.  Have no other computer issues to speak of, i7 7700k, 16gb RAM, GeForce 1080ti, 1TB SSD.  I  can play PUBG, Overwatch and Rocket League with minimal lag on highest settings.  But still getting big lag spikes here.  Wasn't getting them a couple months ago with the same setup.

That really is weird, your computer is better than mine yet I have no lag spikes. Are they just random fps drops? or is it exactly connection lag?

My fps is always at 49-50, never higher or lower, so it seems to just be connection lag.  And like I mentioned, I don't get the connection lag with any other games or apps.  Is there something I should check in my router settings?  I'm not overloading my bandwidth or anything, I can stream twitch and torrent files while playing and it doesn't seem to have any impact on the game connection whether or not I have other stuff open.