Thanks for taking the time to read my post Theoden. I really do appreciate any and all feedback.

I actually agree with both points 1 and 2.
I'm 99.999% sure that she hasn't cheated (I know that every mug that's ever been cheated on says that but she really isn't that sort of person). Although we've both changed significantly over the years, some core principles remain forever in a person, or so I believe. That being said, I do agree that she HAS fallen out of love with me as a partner/lover, and lost all respect for me as a person.
Although I do think she is really after some time alone at the moment, she's made it fairly clear that as things stand, I wont be the man she wants. That to me says that no matter what positive changes I make, I think she's had it and sooner or later, another man will be in the picture. What shocks me is that she isn't willing to throw everything at the marriage to try and save it. I suppose she thinks that as we've been through a rough patch already, she's already done that. She has said that she's well aware that I've only ever done everything for my family (including her) but this appears to count for nought.
As I said in my original post, we had a family holiday back in August and whilst away, she said that she wished that the last instance in March hadn't happened and that she was just having "a wobble". I've tried to explain to her that my recent insecure/depressed/miserable period was a "wobble" on my part, yet she is not able (or willing) to stand by me the way I did for her.

Regarding me moving out, I didn't have to, it was totally my decision to do that. I had though of the good and bad points on this, but as my main goal is to reconcile, I was more thinking that if she'd already mentally checked out of the marriage, that if she physically moved out and got her own flat / started to make a separate life for herself, that my chances of reconciliation were reduced...they seem very slim in any case in her current state.

It was also more for the kids (my D15 in particular) as she has her exams coming up so I didn't want her to have the upheaval of a move. I've only moved to the next street so access is also easier this way. I have to say that even on the day I left, W was still offering to move out and me stay at home.
As far as custody goes, my 2 eldest sons are adults now (one at University, the other at home), my D15 would go with W in either case (not because we don't get along, we are close although I have noticed a significant change in her relationship with me in the time she has spent with W over Christmas), it would really be my S13, who would probably opt to live with me.
I haven't sought any legal council as yet as it's all still fairly fresh. If things seem to be getting no better in the next couple of weeks, i probably will need to. She is saying at the moment, that if she feels no different in 6 months, she wants to sell the home so we can both rent separately. I'm really hoping that it doesn't come to that as that will certainly seem like the final nail in the coffin being banged in.
I'm currently trying to give her all the space she wants, I have sent a couple of messages in the last week but really only about the kids or finances. She is being the Ice Queen right now anyway. I drove past her this evening whilst taking my daughter to dance, she was jogging with her friend. I beeped the horn, the friend waved, blanked by W. I need to learn to not let that sort of thing bother me!
I've re-joined my old gym, joined a cycling club, and am attempting to catch up with some old friends as well as seeing existing ones. I am trying to take care of mind, body and spirit right now. My W also asked me to do this...FOR ME, not for her, which is what I'm doing but I have to admit that even though I know it's wrong, i am hoping that she will see these positive changes and maybe change her mind.

Me 40 W 38
T 23 M 21
S21 S19 D16 S14
BD 19/12/2014
D mentioned 27/2/2015.
I filed 08/04/2015, D Absolute 04/11/2015