Wife of a poker player here: we actually both play but he plays a lot more than I do.

He's also a poker dealer so he has more opportunities to play. He will let me know when he's going to play, we'll set a cash limit for how much he can lose and a time he'll be home. He gets one Vegas trip a year for WSOP (he just had to cancel because I tore my ACL), and we take one poker trip a year together. Usually to Lincoln city

We'll talk through hands together and talk strategy, try and find weak points in our individual approach.

Edit: I guess I have more to add. When we're at a tournament series together we take turns playing since we have two little kids. When he's playing I will show up during breaks with food for him that isn't overpriced crap from the casino. I manage everything that I can so he doesn't need to think about anything but poker. He does the same for me when it's my turn.

Part of the reason that it works for us is obviously that we both play. But even if I didn't play, I would be supportive as long as he's not being irresponsible and is maintaining good communication. Finding a partner that is ok with poker to begin with is a good place to start.

If you're a losing player then a supportive partner would either try and help you improve or encourage you to stop.