pendulosity

noun | pen-dju-lahss-itty | pən\ ˈdyü-əl\ˈlȯs\ˈi-tē

: the tendency of moving from one extreme to the other :

Dale didn't get too upset about Trump's win; he knew the pendulosity of politics would eventually balance things out.

signio

(SSIG-nee-oh)
noun.
When s/he's not your husband, nor your wife, more serious than your "boyfriend" or "girlfriend", and you don't want to use "partner", it's ... your ... SIGNIO (short for significant other).

Hi Jordan, I'd like you to meet my business partner Ken, and his signio Rebecca.

signio

noun | sigg-nee-oh | ˈsig-niō
________________________
\ short for "significant other" \

1. word for a long-term relationship that isn't marriage; used in place of "partner" which tends to be associated with either business or homosexual bonds \
2. stronger than "boy-/girl-friend"; basically like husband or wife but without actual marriage

Hey Jeff, how are you? This is my business partner Giles and his boyfriend Nell, and this is my signio Rebecca.