I agree with Whoopsie (I was thinking this before I read Whoopises comments but they have phrased it better than I could).
I mean I could be wrong (it is not unheard of
), it could be a case of OW ........ but from my armchair, it's not that. (And none of us know for sure.)
I think the trauma of his childhood has made him feel that things fail and if they do not he will do his best to sabotage them anyway. I know someone in real life who does this (but for different reasons).
RE "I really don't know what the hell is going on. I asked him why the romantic weekend away? He said 'because he missed those times with me, wanted to have good memories'. "
So he had already planned to tell you he would go before the actual romantic weekend away?
He sounds very insecure in a way and his 'I'm not worthy' sounds genuine. But what do I know!
You say "I don't know what to do as I'm completely confused. And I'm also left holding the baby as it were. So cross! I've kicked him out for a while until I get my head together. Why would he say this now?"
I think you can proceed at your own pace, but whatever happens, please, for the sake of your dd who will most likely have a lifelong relationship with him (whatever happens with you) insist he seeks personal counselling.
IF he can tackle these issues, personally, he may be able to save your marriage or may be able to have a good co-parenting relationship with you around your daughter or at the very least; a better one that may be possible now.
You mentioned step children, are they his? Are you in touch with his ex wife or partner? It may be wholly inappropriate but I wonder if you were in friend/ good relationship with her ..... if her story of him would be very similar to yours?
I do not think it is your job to fix him, but if you love him, and have a child with him, I think you need to exert whatever influence you have now to request he pursues counselling for the issues that are blighting his life.
I know how fickle people can be, a long time ago had a brief relationship with a guy who was one minute telling me I was the love of his life and he was happy to have found me (all the other women in his life having let him down and left him etc etc) and the next minute was dumping me!
I later discovered (from his own lips) that actually all those other women had been dumped by him but he had managed to make it (in his head) about how badly they had treated him! I was very happy to walk away.
However, we did not live together or have a child together etc etc and I think much as it is not, as I say, your job to fix him, I think you may find it helpful to encourage him to seek help.