My W tried to pull a separation agreement. It was very much in her favour, so I just simply refused to sign it. End of story. You don't have to do anything that you don't want to do anymore. Obviously, protect yourself, but if it isn't in your interests, then don't bother.
I notice you also live in chilly Scotland as well - NDY is also up here, so if you need local advice, I guess we could help with that.
The tiredness is a bugger to deal with. TBH, I've been in an in house separation since April and I wouldn't recommend it. I see your H has cleared off - trust me, this will be less stressful than if he was around. Remember though, if you pay for your mortgage/rent you don't have to leave the house, even if your H wants you to.
M 45 W 52 SD22 S9 D8 BD 6 April 2015 Not living together 4 Dec 2015