You mentioned your husband's texts last week. It may be helpful to analyze them more and try to detect a trend. Is he more responsive during a certain time of the day or week, or during certain occasions (like holidays)?
You know there have been some new threads here in the last week or two that seem to be from people writing from your husband's perspective. Like "I ignored her requests all those years and now she's leaving and I think it's too late..." Maybe you need to consider whether you want to let this situation drag on or whether you want to tell your husband you're ending it, and actually do it, or see if it awakens him to change right before you file for divorce and possibly open a window towards reconciliation. It seems there's the soft approach, which may not bring about major change, or the drastic approach, which may work. Either way you need to make sure you're executing either approach properly. It seems the DB book offers guidance but it's not so specific about situations where the spouse lives and works in another country most of the time and the marriage is already long-distance under 'normal' circumstances. Maybe a DB coach or your own counselor could help with that.
I'd love to visit Glencoe. I hope you can someday live in a cottage in the countryside. I'd love to have a 'stuga' in Sweden, a summer house, or a cottage somewhere in rural Europe. Here in the US we have a lot of beautiful places but sometimes there's a certain combination of elements that we don't have here that only exist somewhere else. Like a certain level of humidity, landscape, climate, architecture, and climate. Here in North America I find the Quebec region of Canada to be beautiful, particularly around Quebec City. Have you been to the US?
I hope the holidays do bring about positive change for either your marriage or for you on a personal level. There are still a few weeks for you to plan your strategy for your husband so hopefully you'll feel confident about what you choose and it'll work for you!