A good sex life is an utmost need in a long life relationship
as you said the only problem is that you both have busy and stressful schedule so that you both cannot find time for each other
For me you should take a break from this busy schedule then go for a small trip and forget all the stress stuffs and enoy the day and don’t think about sex all the time just think about him and his likings so that he will also feel good and you both will spend a good time together, this may help him to feel for you the same you feel for him