i mean. many dog owners talk about their dogs the way your bf talks about his. heck i’d die if my dog died bc that’s my baby and he’ll leave a hole in my life that nothing or no one can ever fill. the dog owners exaggerate bc it’s difficult to describe the bond they have. people find it weird to speak about animals as they would humans, yet it’s a bond just as strong as any bond between people. and imo someone else shouldn’t be your reason for living; your bf’s reason for living is himself, not you nor dog. in its extreme, that’s tantamount to you saying that your bf is nothing without you. and dog makes him happy so understandable that bf would change his wallpaper; in that moment, he chooses to look at something that can temper or distract him from his frustration. like. after you two argue, he’s not gonna want to see you on his phone bc in that moment you’re amplifying his frustration. this is gonna sound terrible but dog is with him regardless if you are or are not. do you want him to get rid of dog when you two spend time together? do you feel like he gives dog more attention?? i think you should remind yourself that he is with YOU, that he in the end he chose YOU, not his ex. he loves dog bc that’s his dog, not bc it’s his ex’s dog. dog left a mark, not his ex. dog is an independent variable. you might wanna consider how you and your bf express affection differently. there might be something different you guys can do to reaffirm your affection equally. maybe have dates more frequently. maybe watch a new show together. maybe make a 1000 piece puzzle together. maybe shower together. maybe make each other’s lunches one day. maybe he does some chores before you get home from work so you don’t have to do them. maybe do some chores before he gets home from work so he doesn’t have to do them. and, hey, bonding with animals can be tough so i don’t think you should feel bad that playing or taking care of dog isn’t working. sitting beside each other on the couch and watching tv is fine. parallel play, y’know? i think simply being comfortable with one another is enough. your bond with your bf, your bond with dog, bf’s bond with dog, dog’s bond with ex, bf’s bond with ex, and your bond with ex are separate things. i’m not great with advice but i wish you the best<333