We found Mating in Captivity, by Esther Perel, to be really helpful in maintaining connection

Anonymous wrote:When you are with her, be with her. Do not look at your phone. Listen to her and look at her when she talks. Ask follow up questions.

Good point. My experience is that there is no substitute for a lot of intimate conversation to cement a relationship. I don't mean about intimate matters. I mean two-way conversation about ordinary stuff, where both people pay attention, listen, ask questions and reply without any judgement or directions in the way of "you should do...blah, blah".

Many flavors of couples therapy - imago might be worth investigating.
I’m impressed that you both recognize it’s an issue and have the opportunity to do something positive.
Better than the cluster that many of us have to deal with !

When you are with her, be with her. Do not look at your phone. Listen to her and look at her when she talks. Ask follow up questions.