The following is meant as a proactive approach, not for the middle of a dire situation - please seek the assistance of a qualified relationships counsellor in this case.
I've noticed, amongst other things, that relationships experiencing problems can take on the qualities of dense or dispersing - either there is a suffocation feeling or there appears to be a void/empty feeling of dissatisfaction.
If it feels dense some weekly fasting can be an idea - take time out for yourself to do your own thing. You will have the energy to do it. Being alone is probably preferred. Being active is excellent.
If it feels dispersing, you can take time out but you will probably prefer the company of others. Don't be alone as it will increase the void. Seek guidance, massages, company of friends, and so on.
You might notice this changes by season and your stage of life.
You can break down every problem by qualities and find an imaginative solution.