I haven't read the whole thread, so sorry if I'm repeating.
We had a big family "to-do" because of dh's cousin getting married and doing the cruise thing. We have 9 children, aren't that close to this cousin, and still the family thought we (and others) were insensitive and uncaring for not going to this wedding when everyone made the effort to go to other people's (local, one afternoon, traditional church) weddings.
The bottom line was, while we were happy for the couple, our family's financial and emotional welfare had to come first. What vacation time we had needed to be for us to relax, not for us to be all concerned about wedding events and etiquette, etc. at huge expense to us.
Every once in a while, we still hear some comment, but rarely. Too bad.
You do what you need to do. If you have the extra money and think it would be worth sacrificing that for your friend, then by all means do...but if you don't want to make that particular sacrifice, then by all means, don't---and don't feel guilty.
Traditionally, going to someone's wedding involves an afternoon of your life and a small gift. Not expenditures of thousands of dollars and a week of your time. IMHO, that's really asking a lot. No guilt for declining.
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