Unusual circumstances

Me and my husband have never lived together. He owns his property & I am a council tenant.
The plan was that he would sell his place & bring his equity to the table with my discount; by virtue of being a tenant I qualify for 35k discount on market value of my property.
After 8 years he has decided that he wants to end our marriage.
I have supported my home financially with him in it throughout those 8 years. i did this in the belief that I was investing in our current life & that I would reap the financial rewards when we joined forces so to speak. He did make ad hoc contributions but no formal arrangement was ever set up.
As things are, he has returned to a property that has increased in value whereas I am left with no savings, no safety net, no security for my children & no provision for my future as it all depended on him joining in!
I found this community because I can''t even afford to divorce him!!
I have been advised by a wiki lawyer that I have an entitlement re a financial settlement & in principle husband agrees. I just don''t know how to begin calculating what is reasonable.
Any suggestions would be gratefully received although it''s a sunny Saturday morning and you should all have much better things to do

I don''t understand how if he lived with you and contributed on an ad hoc basis and has now returned to his own property how you can say that you have not lived together.

Have I misunderstood?

We have spent most of our marriage "living" together but we have never been jointly responsible for one home.

Was his house rented out during the period or at any time?

No - we are both working full time so he just paid his bills (on a mostly empty flat) & I paid mine (on a 3 bed family home with mostly 2 adults and two children in it)

Assets (including pensions) held in joint or sole names minus liabilities form the net value of the matrimonial pot to be shared.

mediation is a good idea. Both of you can sit down and go through the figures together with the help of a mediator to find a way forward that can work for everyone.