Sorry to hear this mate and good luck. I hope you can both get through it all ok.
Having been through it, i’d just warn you to be prepared for it not to be amicable in the end. Having started going through it all still on talking terms, we ended up just talking through solicitors.
As for the DIY divorce, I’d look at getting a pre-settlement agreement written up by a solicitor. That way you know what your both getting/not getting prior to it going any further. It only takes one drunken call late at night and it all goes down the pan.
Good luck