Yup, it's a toughy, and one close to my heart. Dare I say, a lot depends on your other half, and how much they are genuinely prepared to sacrifice in support of your dream. I believe that we don't make sacrifices, because it's what we chose to do, and we get the rewards... but they certainly have to. Mine was very supportive when we first met, and I had just got my CPL. I was still supported when the little one came along, but the 5 - 10 week stints away for FIR, ME-CIR, ATPL etc... placed quite a burden on the other half. Some cope, others don't.
I was lucky enough to do some part-time instructing in the city where I lived, whilst earning money in my other profession. I had planned to go full-time there, but my luck ran out when the school closed.
Simple mathematics suggests that it's very difficult to uproot the 'unit' and raise a family on a SE GA income (unless you have some savings that will tie you over for a couple of years, OR, OR, OR...).
There was a job I went for (I believe I came #2 out of about 130 applicants) where accomodation was provided, and they were looking for a couple/family, so the partner could do office work. Perfect, but unfortunately few and far between.
I was 33 when I started instructing a few years ago, but I have since thrown in the towel. For me and mine, a line had to be drawn somewhere. I feel I got a lot of the hard work behind me, and wasn't far off where I needed to be... but my time was just running out, and for *me* it was clear the time had come to tend to family life in the conventional sense.
Anyway, that's just how the cookie crumbled for me. It definately can be done, as many here have pointed out, and many others that I know have done...
All the best mate... I really hope you get there!