I understand how confusing it is to see someone you love and know so well struggling so much. I'm sure she does have a supreme emotional battle raging within. I think it would be a great idea to get away for a weekend with your BF-- a little break from all of this can only be helpful.
A little 2x4 though... kissing her on the forehead and R talks are pressure and I think it would really be best if you try to avoid those at all costs. From what you describe, I can't really agree that her behaviors and reactions are a roller coaster... to me, you kissing her on the forehead given everything that is going on is super confusing and I am not surprised that she asked you what is going on. If I were you, I would absolutely cut any behavior of my own out that could be interpreted as applying pressure. If you aren't sure if it is pressure, then don't do it.
Think about it like this.. you kiss her on the forehead. She doesn't feel what she thinks she is supposed to feel when her W does that (love, affection, etc). Instead, she probably feels guilty and bad for not feeling what she's supposed to feel, and then that sparks an R talk where she states to you she doesn't think she can ever feel the way you want her to feel. Those probably aren't thoughts you want going through her mind at this point. Also, every time she says out loud she doesn't love you like that it reinforces it for her. (Believe me, this is something I have learned the hard way.)
So--- be sure that you aren't doing anything that applies pressure and pushes her further away. No kissing, no hugging, no affectionate touches. No saying ILY. Be cool and detached. Give her space and use the space you've gained to GAL.
(((Mar)))
Me (46) H (42) M:14 T:18, D9 & D11 4/19 - 12/19: series of escalating BDs 9/20 - present: R and piecing