my 2 cents
kudos for considering this at least and weighing things out
those us of in the field can get a bit jaded, things 'aren't like they used to be' on multiple fronts, but it is still a great profession, and even though it is cheesy to say I would argue to some its more of a calling
the road ahead won't be easy. indeed getting in will likely be the hardest part (and actually here I'm not sure your age or experience will be a detriment- some schools may even look kindly on this) but you still need the marks and the prereqs etc. and prepare that you may not get in on your first try
quickest way in and out (once in) would be 5 years I guess at a 3 year med school (such as UofC) then family medicine
in my class (and this was a long time ago and in a traditional med school) had few 'mature' students but there were definitely some in their mid to late 30s- they were also raising kids while doing it and survived, it is doable
I know someone who did what you are describing, I think he would have been in his 40s (he's still in the system) . at this point many specialist residents (especially those pursuing academic careers with a research component) don't start practicing until 40 so that in itself is not unusual
there will be a few years that will be a grind, and where a younger person would probably be better suited. this would be your clerkship years and if in family med probalby first year of residency so you will have 2-3 years that are more relentless (although I gather work conditions and restrictions have improved over the last quarter century
)
I would strongly resist the temptation to go 'offshore' ( and not just the Caribbean, but once you leave Canada and then the US getting a residency spot becomes really complicated)
good luck