From everything you say, when Frank is on top of his game your wife is ok. I read that, as when you are on top of your game, you are helping her as she feels secure and contented and she does not feel the need to run.
When you struggle she struggles and wants to find someone/ someplace else to find comfort.
Srikes me that you have to heal yourself, which you know, and if she happens to be there at the finish of your journey then that's all well and good but if she isn't, then you know her true worth, and possibly you shouldn't be with her if she cannot stay the course. When you are at a low ebb the worry of her drags you even lower.She has to want you for wanting you - warts and all; not just for the good times.
Saffie me 46 H 46 M in 1986 D20,D18,S16,D13 H's A 01/05 to 07/06 H recommitted to M 07/06 renewed vows 09/06 Going from strength to strength