when i told my parents my touring plans, they seemed cautious but okay with the trip. but when i mentioned that i wanted to tour solo, they both freaked out.
but that is what parents and family members do. so here are a few things that i have noticed seem to start turning there feelings in the right direction.
1: i invited them to come along. even though i would prefer solo, if they came, then they could see how safe it was. of course, i knew neither of them would accept the offer (although dad has mentioned he would like to do montana with me) but even if they did, it would still be a great time.
2: site precedent. each of my brothers spent large chunks of time in countries much more dangerous than the united states (where i am planning on touring). one brother spent two years in west africa. and another a year in europe. if they were both completely fine (even though they spoke the language) there, how can a three month tour across the united states be any worse?
3: keep them informed of how your training is going. when i told them about my first century a few months ago, i think it helped them realise that i was serious. it also proved that long distances can be accomplished safely, even if you are biking through new areas (even without a map).
4: this one seems strange even for me, but we had a discussion of where i COULD ride. if a trip across the US was too much for them, what states were okay? well, i got more information than they realise. it was okay to bike in my own state (which is a good thing!), and in the state where they live in, as well as a few others. since our states touch, and i have their "permission" so to speak, i'm biking home for thanksgiving! won't they be surprised when instead of picking me up at the train station, i am on their front porch with my bicycle! sure, they might freak out a little, but all will (hopefully) have gone well and i am sure i will have a few good stories to tell about the ride. with a short tour under my belt, it will be easier for them to accept a long tour later.
glad to hear you are not taking a gun also. even after your trip i wouldn't tell them of anything bad that did happen (and hopefully nothing will), but you are right, mosttroubles on a tour do seem to be bicycle mechanics related. if they see that you can fix any part of your bike, then they will know that you will not get stuck in the middle of nowhere and that you will always have a way to get to safety if you need it.
still, they will worry. if they can't give you all the support you need, that is there decision. i am sure they will support you in the end.