Regarding your son, we faced a similar dilemma. Our son was 17 when I first started getting the itch. We started getting educated, sailing more, and talking about it, I'm guessing at about the same time, but certainly by the time he was 18 and entering his freshman year. We departed when he was 20 and a junior. During that period, we kept him well informed of our plans, in a matter-of-fact manner, but not in a way that could be perceived as granting him a veto. (That doesn't mean we wouldn't have aborted or postponed our plans if we thought it would be a problem. We certainly would have, but not by giving him a message that it would have been up to him.)
We told him the same sort of things -- we flew him (and his girlfriend) to where we happened to be for holidays, and occasionally we were back home, too. We made sure that he was well informed about how to get in touch with us (including sat phone
, if necessary), and we made a point to Skype him whenever possible, as well as email
We had planned to stay out for 5 years, but that got cut short when the economy (and our investment income) tanked. Now, fortunately, although I was 53 when we left, I have a rather esoteric profession and was able to quickly resume work. But, if the work/income/savings business is iffy for you, then you might want to seriously think and plan some for that. (We did get 2 years in, and had a great time, just not as much as hoped for.)
Back to your son, though. The process of individuation is not necessarily consistent between different people, and different children
may need different things at different times. Only you (with talks with your son) can assess that. Having recently lost
his father, though, may have complicated that a great deal.
I suggest you read and think about the following two articles that describe the developmental tasks that your son has been facing, both recently and in the near future. Think them over and do a little informal assessment. It might help you figure out where he stands.
The Successful Parent | Early Adolescence: The Point of No Return - Part I | thesuccessfulparent.com
Trial Independence (18 - 23) = Struggling to catch hold | Psychology Today
There can be some big differences between 18 and 20. At 18, and a freshman, he's going to be exposed to lots of things. Kids
that do well already have a well established sense of self, their values, what is acceptable behavior (for them) and what isn't. They also have relatively good impulse control - even though sometimes they won’t resist the impulse! That's part of it, too. But, they've got enough "sense" to recognize bad situations before (or soon after) they get into them, as well as enough stick-to-it-tive-ness to persevere with work/studies without needing parental structure. Kids
that don't do well don't yet have those qualities. (It's part of development, and maturation just happens at a different pace.) They might also have problems controlling alcohol/drugs, risky behavior, and regulating their emotions. Also, keep in mind that the period between about 15 and 25 is a time when the onset of many serious mental illnesses is at a peak. So, if any of those things are present, then great caution is warranted and the security
of Mom will be even more important.
By 20, most kids are well along in that process. Assuming none of the really hard problems are present, he will be much more likely to view your adventure as a cool thing -- AND, you are more of a role model than an authority figure. That's an important difference, as you taking care of yourself and following your dreams becomes something for him to emulate, rather than resent. If you can accomplish that, then you will have earned several gold stars as a parent.
Now, allow me to brag a bit. Our son handled it all quite well. One of our parenting strategies since he was very young was to allow him enough leeway to make his own decisions for himself, as they were developmentally appropriate, while challenging him just a bit beyond. When we first started talking about cruising, he was a bit taken aback by that (even though, at the time, he certainly wouldn't admit it!). But, we could tell that the wheels were turning! Shortly after, still when he was 18, he announced that he had decided to go into the Peace Corps after finishing his Bachelor's degree. By the time we were set to throw off the docklines, he was quite independent with his studies, making good grades without any feedback from us, had established (and lost
, and recovered from) a couple of relationships, and had a good plan for himself, of his own making. Shortly after our return, he graduated. And, yes, he was accepted into the Peace Corps. In the months before his PC departure, he bicycled solo across the US. Since returning from the Peace Corps (If you don’t think that’s tough, then imagine yourself being set down in a very different culture, with an unwritten language you don’t know, pretty much by yourself, eating food
you’ve never seen before, no electricity, no running water
, and an important job to accomplish – in 27 months. That’s pretty gutsy.) Anyway, he faced the awful job situation for young adults and persevered. He's now putting himself through grad school, paying for it all himself and keeping a decent savings account, too. And about to marry a fine young woman, too. Yeah, we’re proud.
Now, it wasn't us taking off on a cruise
that did that, but I do think it helped. When he was ready for it, it gave him the message that he was capable of dealing with life, on his own, and that we were confident in his ability to do it. That, in turn, resulted in him feeling confident, too, and that makes a world of difference.
Sorry about the long length, but I hope this helps.