Your priority is finding a home for you and dd and you're best advised to focus on this project.
As for the 'stuff', bin all obvious junk without a second thought.
Until such time as you know what you may need in your new home, box up those especially treasured possessions that you wouldn't want to be parted from even if you were reduced living in shoebox/on a park bench and then set to work on boxing up the remainder in room categories (kitchen, living room, breakfast room, dining room, etc) listing the contents on the outside of each box.
Take what you need to your new home and put the remainder in storage to be retrieved and properly sorted through/disposed of once you have made your mark established yourself in your new environment.
Until such time as you have the inclination/leisure/will/emotional strength to stroll down memory lane, see objects for what they are - inaminate items that only have as much meaning as you invest in them and which, in themselves, have no power to cause you pain.
Having moved house umpteen times on 2 different continents, I have a virtual warehouse in my memory bank that's packed to the eaves with goods that have passed through my hands and are no longer in my possession but I only visit it if I happen to come across an item that reminds me of what I once owned and loved.
As for ptm, detach detach detach before he sucks you back in. Revert to the former status quo of minimal communication by email. Don't accept phone calls from him or make any to him, and do not engage in dialogue on any matters other than those which have to do with financial settlements etc - but isn't your solicitor dealing with these issues?