a doctor will not help you here. a marriage counselor is going to be someone to see.
i don't see this ending well though for you, never get into the habit in a relationship of not spending time with each other. i don't care how busy you are. almost dedicate a minimum of 2 hours a week of just 1 on 1 time. if you get into the habit of not doing this, that is when you go 1 week without sex, then it becomes 1 month then it becomes 1 year. i know people who have been married years who have had sex like 3 times total
there is also the possibility of him getting sexual satisfaction other ways like porn or other women/men. everyone always assumes in a sexless marriage the person has something hormonally wrong with them. in all my years this has NEVER been the case. but one party has the wishful thinking that it is hormonal and just running hormones will fix it