How can I help him ???

Well my partner rang me the other day in a bit of a state saying he thinks he might have adhd . So I asked him why he told me all the symptoms and everyone off them clicked . I said ok well maybe go to the doctor he said ok but still hasn't made the appointment this was last week . This is him all over biggest procrastinator, I didn't even know what the word meant till I met him . Our relationship has been so up and down due to what I though was him been lazy , inconsiderate  , not listening and never finishing things eg: our bathroom he said he would paint has been half done for 5 months now !! He is really upset about finding it out what he thinks is adhd but deep down knows it is . I don't know what to do he is fighting with me more than ever it's like an excuse for him . He is really down about it I'm worried about him. He doesn't want me saying it to anybody  either .  Any advise what I can do ??