I think you need to speak to a coach. You're in a unique position here compared to most.
You separated four years ago...your W or EX is pursuing you fairly consistently and you're at a loss how to deal with it. You don't want to push too hard, incase she bolts...yet you need to show strong leadership.
You say you don't mind her decision either way but you're on here telling us about her every interaction no matter how small...you are very invested in this.
The advice here I think has mostly been to get to know her again, go on 'dates' initiated by her (I'm in the minority as I believe it wouldn't have the sky fall in if you proposed a date...but as I say...a coach would know better...), no drunken sessions, show your leadership side, let it unfold in a natural way as if you'd met for the first time. And if you have something to say...answer those texts.
If you have no expectations, the journey could be a beautiful one. If you have expectations then all you're going to be looking for is those that go unmet.
My advice is to speak to a professional.
Me 50 H 48 S 23 S 21 D 19 Together 31 years Married 25 years Separated April 2009 Reconciled 2010 Separated September 2017