I'm in a bit of a tail spin and I could really do with some advice 
I have GAD (generalised anxiety disorder) and made a mistake at work. It wasn't a big deal but if it had escalated it would have counted as misconduct and I would have been disciplined formally. It was a genuine mistake, I came clean straight away and I was completely honest. It didn't escalate, it was all sorted out and it's now gone away completely.
However, when it all kicked off I panicked and applied for a lot of jobs in my field. A couple of days later I got replies and a few interviews.
One interview was for a job a fair few levels above my current role and for £35k a year, I'm currently on £26k so it was a pretty big jump (I'm up north and only 26 years old so it's a lot of money to me)
I decided I had nothing to lose so I went to the interview. Long story short, I got offered the job on the spot and the lady interviewing me was super super excited about my interview and technical knowledge etc. I liked the environment and it's a great opportunity.
I currently drive an hour to work every day, the new job requires a 30 min drive then 40 minutes on the train so not much difference there.
In the meantime, I'm supposed to be getting married in April but FiL2b isn't going to live that long so we're having to move the wedding forward to October/ beginning of November. We found out about his prognosis the same day I found out I got this job.
So now my anxiety has kicked in because I've got too much in my head and I can't separate my fear over FiL and sadness for DP from my anxiety over changing jobs and general stress of the whole situation.
Part of me wants to turn the job down (I sign the contract on Monday) but the other part recognises I might not get this opportunity again and certainly not for a long time.
The other thing: I have 4 years at my current company and would get 6 months full paid maternity. DP and I were planning on trying for a baby straight after we get married but obviously that would now need to wait a couple of years now the wedding is moving forward and with me planning to change jobs. We can't afford for me to go on maternity leave unless we save as I'm the main earner.
I realise this is a lovely dilemma to have and I'm incredibly lucky to have this option to move jobs to a significant step up, but the other stuff is really confusing matters and I just don't know what to do?
Do I take the job and stop worrying?
Is anxiety in this situation normal or is this a result of the GAD and I should try and use my CBT to get my head around it?
Is the timing just really awful and actually anyone would turn it down with everything else that's going on?
Argh.