This is very familiar.All I cared about then was marrying my wife, and I let the preacher come up with the vows without vetting them, and of course one of them was keeping myself only for her until death.
However, we both wanted the truth, and when polygyny came up we both were open to whatever YHWH had for our life. That vow is fine for me, and I had no desire to hold my husband to a non biblical vow, and now there is someone else making our family richer....and I don't mean with money.
There isn't as much shame in ignorance as there is in refusing to hear the truth.
My dad loves quotes like this one..
Accept nothing that is unreasonable, discard nothing AS unreasonable without proper examination.
If YHWH said "Come let us reason together" I consider such conversations to be among the most edifying.....to truth seekers.
It sure weeds out the shallow and insincere though!