Yes, it absolutely is! When you start working on yourself, the light, the joy, the passion will naturally flow out of you to your partner, and he/she will begin to notice this change and want to give more to you. It can take some time, but it can happen. The other way is of course, to take a one day intensive or for the full monty, a full weekend intensive where you really kick start the relationship and reset it to the day you got married! These intensives can be absolutely life changing when done in the spirit of love and joy. For more information about intensives, feel free to reach out to me! Also, you can read my article on here, "when is it Time to Call it Quits? I wish for you a life filled with Gratitude, Abundance, and Passion!
If you feel like that will help your marriage I'm all for it. But make sure that you try other methods like at home or in office counseling, relationship building exercise and othe ractivites that could help your marriage. Couples retreats tend to be very expensive. It's like a vacation that includes counseling and therapy.
The fact that you are wondering whether to look for a marriage counseling retreat probably means that you are wanting some help in your marriage. Sometimes married life can become so hectic with the day to day demands of juggling responsibilities that you begin to feel as if you are living past each other like ships in the night. In a case like this, a marriage counseling retreat could be the best thing for the couple, where they can take time to relax and be alone together in a quiet and tranquil setting, receiving input and counseling to restore and refresh their marriage relationship.