DV6...I haven't been on here in a while now...BUT when I read your last post:
Have you talked with Jack about how you feel when you are not together AND what you want instead? If you have, what has been his response? If not, why don't you talk with him about it when you two are together?
Perhaps it's just needed for you two to set expectations and find some understanding for when the two of you aren't together. Also I'd be careful from linking your current feelings of being alone when Jack is not around to your marriage experience. I know from my own experience it's easy to try and create parallels between the two, think OMG this is the same thing over again, run, run...Have to remain mindful of treating this R as it's own independent experience.
