I'm not sure where in the world you are, but here in the UK we have two different legal systems - one for England and Wales and one for Scotland (goes back to the act of union!). In my part of the UK, you can legally get a separation order which is administered by a Sheriff (judge) which effectively dictates what you can and cannot do and who has responsibility for the kids etc. My W, because I wouldn't move out or sell the house originally, wanted one of these - I simply refused.
We are technically separated, but not legally so, as we are not bound to adhere to any court orders (none have been made) and we make our own decisions on childcare, maintenance etc. I suppose if it got ugly, either one of us could get an order, but my W called off the L in August, so I don't see the need for one.
As for assets, as we're still married, of course, if anything happened to me, my W would get everything (pension etc.) and vice versa. I did contemplate writing her out of my pension etc., but I didn't feel the need. Obviously if either one of us decides to go to full D, this would need doing, but it would be part of a settlement.
As for an R, I wouldn't say being separated has harmed any chance of this. I see signs from her that all is not well in her life, and what she longed for hasn't met her expectations, but it's not up to me to start that ball rolling. Time, they say, is a great healer, but having lived through an 8 month period of in house separation, I'll tell you now, despite being told not to leave the marital home, I wouldn't recommend it. The anxiety and stress was unreal and although I miss W and the kids every day, the lack of pain and suffering is a real godsend.
M 45 W 52 SD22 S9 D8 BD 6 April 2015 Not living together 4 Dec 2015