On 07/12/2018 my laptop displayed a notice that my "computer is slow to respond" and asked if I would like to "disable all add-ons or extensions" [I am paraphrasing here]. I agreed to this, in order to speed up the computer.
I thought I would be able to reload MetaMask using my seed words. However, when I reinstalled MetaMask and entered my seed words and my password, things got confusing. Eventually, I was able to access the account using my password, but none of my ETH or tokens showed up.

I was able to access MetaMask but, when I enter my Password [which I never changed during this process] all I get is an account having no ETH or tokens.

MyEtherWallet shows all my ETH and tokens but, they are no longer connected to my MetaMask add-on/extension.

Until this account-recovery problem appeared, I was completely OK with MetaMask. But, the recovery process leaves me unhappy and the potential [or real] loss of my ETH and tokens makes me poorer.