I will share with you what my mother-in-law used to do with her dogs. I'm not saying that you are doing this because I don't know, I'm not there.
She had a chihuahua that she adopted as a senior. When he would be on her lap and someone came over, he would bark at the person, and she went Now now, and stroked him. Her reasoning was that she was calming him down. What the dog thought was that she *wanted* him to bark at the person. So she did more stroking and talking softly. It's very hard to have a conversation with a dog barking so at one point I just gave him a look and very firmly said Stop it. He gave me a look, and stopped. My m-i-l quickly went to stroking him again and he took his cue and went barking his head off.
She did not understand that she was reinforcing the barking and soon you could be sure he would bite if anyone got close. I think he may have bitten some family members that mistakenly leaned over to give her a kiss or hug.
If there is a behavior you don't like, say a firm NO and put him on the floor. The lap is a privilege to earn and he's guarding his person and spot. On the floor quick at the first moment. Try practicing with your wife coming up beside you so that you are ready to act the split second he gives an indication he's going to 'get upset'.
When it's time to feed him, both of you should have turns feeding him and making him go into a sit before he gets fed. Going out for a walk, he should wait in the doorway and let the person go through first, because top dog goes through a narrow opening first. Practice a sit and calmness with the door open before heading out. Reward calmness when you have the opportunity.
I hope these are things you can try and will help you. Keep us posted.
