I might have actually shed a tiny tear at some of the nice things people said above. Thank you everyone 
I know mumsnetters love an update so....here it is! I got a reply to my email from, let me start calling him, Jack (not his real name). He made a jokey reply which was nice, I am enjoying laughing at the moment. He told me his phone number hadn't changed, but I don't know if or when I ever called Jack in the last 20 years, and I don't have his number now. I couldn't let him think I had his number, so I had to reply and tell him, and I told him he could give me a missed call then I could save his number in my phone 
I sent that late at night, just because I had been busy all evening, and I got a 2 word text this morning "Jack's number". There was a bit of banter exchanged which was a fun distraction from pretending to work from home on the last working day before Christmas.
The reality is I am super busy. Setting up a new flat has been hard work, I am working full time, and have 2 kids. Christmas will be down time I really need and the kids will be coming first.
The last few weeks have been transformative. It was horrible telling everyone I had split with my husband, I could only tell so many people per day because even if I held it together in front of the person (or virtually in front of them over the phone etc) I would have a good cry afterwards. One amazing thing that came from that was so many people said such wonderful things to me...I was told I am funny, people want to be around me, I am an inspiration, I am courageous...things I haven't felt myself being married to a man for so long, who although I believe loved me, was not in love with me, wouldn't touch me and would frequently seem irritated by me. I felt like a husk of a woman, but a slightly overweight husk if there could be such a thing, and all round generally a bit of a hopeless loser!
I feel ready and want to be that person other people see me as.
Small things have made my confidence grow. There are so many 'jobs' that get divided in a marriage. I had never put air in the car tyres, yesterday I needed to put air in the car tyres. I took a deep breath, googled it, it said the required tyre pressure was usually on the inside of the car door, and you know what, I put air in the tyres!
I hadn't set up a home internet connection since the days of dial up, I thought it was a great mystery. Turned out it was just plugging a data cable into the wall from the modem and a power cable. It was practically the same as when internet was dial up!
I have lifted heavy furniture that I would have left to my husband to move - I am covered in bruises, but feel a super strength has come out.
All of the that is in addition to pleasuring myself everyday since Sunday! I can't believe there are people out there that do this all the time and I have been missing out.
A female friend at the party on Saturday said to me "if there are jobs you can't or don't want to do, that is what Airtasker is for!"
My new flat has come together so well. I moved out of a big 5 bed 3 bathroom house, which was lovely, but I chose to move out because I couldn't bear the weight of a so much 'stuff' dragging me down, and the cleaning and gardening on my own after working full time. My ex is quite consumerist, as is the family he comes from, so it's one area we clashed - he can have the big house full of stuff (I will get my equity out when the time suits us both, I don't want the kids to have to move from there now because they love playing with the neighbours).
I wouldn't let my ex see the flat before I had made it into a home, I didn't want pity for 'moving to a small flat'. He saw it for the first time tonight, I think he was actually blown away, a tiny bit jealous, and it was pretty clear I don't need him. I pulled together all these pieces that he would never have vetoed and it feels like a true reflection of me, and a home. Tonight when my 8 year old went to bed, he told me it is perfect.
The text messages with Jack are a novelty, and lots of fun, even if it goes nowhere it is helping me get 'me' back. I genuinely would not have sent the second email without the prompt from @StarlightLady, so thank you 