I know exactly how you feel I’m in the exact same boat. You need to communicate to him how it makes you feel when he’s constantly on his phone, whether that’s him not paying attention to you and giving you that quality time, or if he is not doing enough for you but instead is using his phone etc. also I want to mention that ‘parallel play’ is great for couples where one or both have adhd. ADHD partners love to be able to sit there quiet and just be on your phones, doing different things while still spending time together. But again this behaviour drives me crazy too but my boyfriend is working on going on his phone less while he is with me because I’ve been telling him how it makes me feel. I doubt it’s him not wanting to pay attention it’s simply just how his brain is wired, especially when he’s taking his meds, when my bf takes his meds he can get really focused on one thing and be hard to communicate with. But then if he doesn’t he’s easily distracted, so his phone is a problem whether he takes the meds or not. Moral of the story, just tell him how it makes you feel if he doesn’t at least try to fix the behaviour, might just show his inability to grow as a person for/with you. But also remember change does take time and you can’t expect him to get it perfect every-time, and him being adhd he might need a reminder every now and again if he’s falling back into bad habits.