I worked with a therapist who was reeeaalllly good at grief issues, and so I often asked him for concrete things I could do to help the process forward. You might ask yours to elaborate on this.
Some of the things I did were
- writing morning pages (from The Artist's Way)
- making a list of the good things and the bad things that had come of my relationship, to get clear on everything
- thinking about things that felt missing in my life, and doubling my efforts to find them in other places
- crying when I felt like it, even if I "wasn't supposed to"
- doing things that involved physical exertion, which usually brought me to a more peaceful state
- reading recovery material on grieving, like this: Grieving process: What's normal? - MayoClinic.com
- identifying the things that I was grieving, and trying to help OTHERS get through similar situations
Any material on grieving can be helpful to you, chrysalis. Wherever something talks about the "loved one" you lost, just substitute in your mind the "loved one" that was whatever thing you thought you had in your marriage before all of this began.
The good thing about this, truly? Unlike someone who has died, which is kinda final, it is very possible - even likely - that you will be able to bring your happiness and joy back from the "grave." It's not gone, it's just been sleeping.
Hugs,
GL