ISFP 6w7, would bet on it.
No clue why people even suggested ESFP and ISTP.
There is no way that anyone that gives an ambivert vibe is either of these two types, connecting tomboy to ISTP is selling stereotypes 101 and ESFP are the quintessential extrovert, not even a good binge on Xanax could change them so much, even after settling down. Probably writing cliches 101 here but think about it.
ISFP come in two different flavours, the brooding, artsy, humanitarian emo and the outgoing, physical, rebellious buddy. ESTP could work but this quote-> "In the positive sense, my wife has a very sweet, loving character, but she can use the sweetness to get her own way. I prefer that over those who try to use vinegar instead of honey to attract the "flies." just screams ISFP to me and 6w7 could be easily seen as outgoing, party people. They just need to recharge.
She seems pretty avoidant of conflict, being consistent in her inconsistency and letting her kids off the hook. Plus the way she dealt with her family screams Fi and not Fe to me, she didn't try to emulate her sister to get some praise and her way to confront her parents was to work hard to prove them wrong while still being her rebellious self. If that ain't a passive aggressive Fi middle finger, nothing is.
Many ISFPs are quite the feisty tomboy, they are pretty damn grounded and earthy in their freedom seeking ways.
Those were my two cents, your wife sounds rad.