>>149380090
To put an end to Crystal/Johnny and write Crystal out of FF, letting writers have a single Johnny again, and to write Pietro out of Avengers, so Wanda, the more popular twin, could develop more without her overbearing brother around, and so they two of them didn't have to be treated as a package deal anymore.
The marriage was a way to just retire Crystal and Pietro as characters, though that didn't last. The relationship leading up to the marriage mostly taking place off-panel, and them largely being written out of comics for years afterwards is why few people were invested in them as a couple.
>>149382371
They were at their best in the 90s, both a little older and wiser and trying to make it work, but Marvel just had to throw it away to revisit a love triangle that had already been done.
