I have often read through the many posts such as this one and it's responses, where the person who is supposed to be their bird's owner, the one who wanted the bird in the first place ends up not being the person their bird has chosen as "their person", and felt so relieved that I am currently single and live alone in my house...And then also scared to death at the same time about what will happen when I again meet someone...
I was married for about 3 years, and at that time I had only some Budgies and Cockatiels that were breeding-pairs and not pets, and my spouse was not at all an animal person, which is one of the main reasons they had to go!!!They didn't even like my dogs, which at the time included the most intelligent, well-behaved, well-trained, loving Australian Cattle Dog in the world, and a fat, wrinkly, cute as a button lap-loving Pug! How do you hate a Pug??? Well they did, so you can imagine how they felt about the birds! I remember getting-up every 3 hours during the night to hand-feed chicks (I would sleep in the spare bedroom during the first 2 weeks after pulling chicks from the nest-box, so I wouldn't wake them up multiple times throughout the night), and I remember sitting in the chair at 4:00 in the morning, hand-feeding Cockatiel chicks that were only 3 weeks old, and having my spouse walk into the room after getting up to use the bathroom...They walked in while I had a little 3 week-old Cockatiel chick in my hand, feeding away, his little crop blowing-up, the most adorable thing in the world, and my spouse walked over, bent-over and looked at the chick, and then said "That is the ugliest thing I've ever seen in my entire life. I'd just flush them...". That' was it for me...
But I do often wonder how I would react if when in the future I get into a serious relationship again and have the person move into my house, and it ends-up that Kane, Duff, Lita, or my little Bowie would suddenly start giving their affection and love to my SO...I honestly don't know if I could handle that...Seriously, that makes me nauseous and causes me anxiety just thinking about it...
So I give all of you who are dealing with this issue great credit for being able to handle the situation, because I honestly think that this issue would most-likely cause my human relationship to eventually break-up, and I don't think that it would take long for it to happen. I couldn't have my own human children due to health issues and finally a complete Hysterectomy/Oopherectomy, so my animal kids are quite literally my children and my family...And if Bowie or Kane or Lita or Duff suddenly stopped allowing me to touch or hold them, stopped flying to me when I call them, stopped wanting to sit with me/on me at night while I read or we while we watch movies, or if Kane suddenly stopped wanting to constantly go out with me hiking, biking, shopping, etc. in the summertime, I would be absolutely crushed and just a wreck...So you are all to be commended for being able to be strong about this issue and hang in there...
There is always hope that you'll be able to work out your issues with your birds, and it should be said that sometimes when they switch their preference from one person to another living in the home/Flock, it can actually be related to hormones raging; so it's quite possible that it may be a temporary phase that your bird is going through, and that as their hormones calm down their attitude will change. However, it's very important that you don't give-up and that you keep on doing everything the same way as you always have, if not being even more persistent in being the person that does all of the "Good Stuff", while your spouse/SO who the bird has taken a liking to isn't the "Treat Person" or the person who does any of the things that your bird loves the most...
That being said, remember that if your spouse or SO is home all day long with your bird and you are not, you really do need to think about what's best for the physical and mental health of your bird...You don't want your bird locked inside of it's cage all day long, every day, when your spouse/SO is actually there all day and your bird could actually be out of their cage all day long. I would not have your spouse stop letting your bird out of their cage all day long, but rather let them out and keep an eye on them of course, because they shouldn't be unsupervised and flying all over the house doing whatever they want, but your spouse/SO also doesn't have to have the bird sitting on them all day long, petting and scratching them, playing with them, feeding them treats, etc. either...It's about finding a happy medium and making sure that whenever you are at home and with your bird that you make the very most of it...