Marilyn one of my siblings is an academic and says that academic politics are so nasty because the stakes are so low 
I finished my first (AHRB - as it was then - funded) in the late 90s. I then went to work in the field, one that's notoriously ill - paid, though this didn't require a PhD and then drifted into work in other areas. 15 years later, did another PhD in social sciences and have been an academic since 2009. The second one was way, way harder than the first one: probably because I was under no illusions about the process, but I needed it to progress in the work I was doing (didn't intend to go into academia at the time).
I'm now a Prof, but it's been a slog, to put it mildly, and I walked out of my previous institution earlier this year. I took a number of months off, and was extremely lucky to be head-hunted for my current institution a few months ago. I am aware this was incredibly lucky: I'd intended on leaving academia when I had left earlier in the year.
A career in academia doesn't just require intellectual ability and hard work: you have to also be extremely lucky. I tell my students that they should only contemplate a PhD because they couldn't imagine not doing it - no matter how much passion you have, at some stage, it will turn into a slog, and you will likely have plenty of long, dark nights of the soul. If you don't have children or a partner, it's easier in terms of managing your time, but then you have less support at home and no one to share the bills. An awful lot of people are fully funded and don't make it through to the end, and it can be extremely isolating. If you are a perfectionist or a procrastinator, think very, very carefully before starting. If you are both (like I am) you're making a rod for your own back!
Finally - hands down some of the dimmest people I've ever met have PhDs - it's an exercise in meeting certain requirements to pass, rather than a benchmark of intellectual brilliance. If you can treat it as this exercise, you'll be much more realistic about the process.
Good luck!