Well, as far as the monster thing goes, it actually is a coin flip thing. So even if you've found your partner, if they summon your monster, only one of you should be affected.

...I mean, supposedly, I feel like no one really has that good a handle on what's going on here, so I don't think there's any guarantee we won't find out in a few weeks that they were wrong about that, but. Seems hopeful, at least.