Ok so I am in a similar situation and my mortgage is a bit under 4k. Yes it’s scary, but I have a couple of comments:
People will comment from a place of good intentions and say this is crazy money, but that is benchmarked by their own earnings. It is all relative. Depending on the exact split of your earnings and tax situation/thresholds let’s say you’re on a post tax take home of £150k. 60k a year mortgage is affordable on that, and frankly your job situation is more stable and guaranteed progression than most. Your other expenses will be comparable with other people ie a day fare zones 1-2 costs the same whether you make 30k or 300k.
There is no point taking advice from someone with a £600 a month mortgage and a 30k salary because the world has changed and if you’re looking to buy in the capital, this is the situation people are now in. You can still save a lot on that salary and have a nice lifestyle (albeit less so if you are paying for childcare or school fees). One bed flats on my road go for £1500 a month now (And I live in shock horror south east zone 3), so buying a 4/5 bed with garden and parking is clearly a better deal. I also think there’s a big argument for skipping the ‘starter home’ when stamp duty is going to cost you tens of thousands and leasehold is so punitive.
As for hating your job: I understand that the corporate slog is not to be sniffed at (as I a fellow corporate slogger), but you have far more options than someone with fewer skills and qualifications. You can always sell, or take a lodger if absolutely necessary.
Finally, the bank won’t let you borrow if they don’t think you can afford it.
We are all susceptible the the ‘extreme anchor’. I remember feeling horrified that my first house was going to cost at least 500k if I stayed in London (and then ended up costing more than 900k, so there we go). My parents expressed similar horror that they bought their third house for 250k, and had done so even before that when they bought their first for 50k. Anyone who says that what you’re doing is crazy has no concept of the situation we are now in, and if you want to get on the ladder with a family home, this is what needs to be done.