How would you resolve this marital problem?

[wind_updoll]

I think marriages go through phases like this, but yours seems extensive. Plan a dinner date, nothing fancy, but let her know your plans in advance. Bring her a simple gift that you know she would enjoy. Try to be pleasant, and repeat this nice a week for a month. If nothing changes, have a game plan of where you want to be in 3 months, then have a conversation with her about separating.
Sometimes people don't know what they have until it's gone, unfortunately, and if you're opposed to marital counseling, there are few options,other than accepting it.