The marriage retreat may make him reconsider couples counseling.
We read Dr. Phil's Relationship Rescue book together. Also, the Love Dare /Fireproof your Marriage is a great resource for couples do together. If he refuses therapy, then at least doing something like this together can really, truly help.
And yes, our marriage was truly terrible, we only went to 2 or 3 therapy sessions, but we worked our butts off to re-date, communicate and learn to appreciate and care about each other, and how to show our love and respect in a more healthy way. Has been SOOO worth it.
Also, watch these 3 short videos together, only about 3 minutes a piece, but a real eye opener on how to treat each other and that there can be hope:
How do I love thee:
http://lds.org/ldsorg/v/index.jsp?autoplay=true&index...
Marriage and Divorce;
http://lds.org/ldsorg/v/index.jsp?autoplay=true&index...
Expressions of Love, couples share their ideas on expressing love for each other:
http://lds.org/pages/expressions?lang=eng