Phew, my head feels all messed up, thanks for all your comments.
Laura ? I'm not sure that I could expect DP not to have a say in how I parent, it has to be a 50/50 thing surely? I know DS and I were here first, but now we are trying to live as a family the 3 of us. Obviously if I was very strongly opposed to something I wouldn't go along with it, ? but wouldn't the same thing apply in a 'normal' family (ie without step-parents). I can't imagine parents always agree on how to parent.
DP is great in the sense that he can give me a more detached view of things as he is far less emotionally involved, he can be very logical and objective which at times I find really helpful, like the other night when I was upset and didn't know how to handle the crying at bedtime thing. I just wish his logic wasn't always so cold!
Mumpbump - thank you, it's reassuring to hear that others have the same problems.
I have to say DS is a real 'mummy's boy' but aren't a lot of 4 year-olds? Especially where they are the only child? I have difficulty in drawing the line because I feel so guilty that his dad and I split - I feel he has had a rather mixed up few years and I don't want to do any more emotional damage to him. Maybe I do end up being a little softer than perhaps I otherwise would (although as I said before I don't think I'm a pushover) to compensate - which is what drives DP mad. I can't decipher whether DS acts the way he does at times because he's just 4 and playing up a bit, or because he is genuinely mixed up/distressed/in need of reassurance.
Makemineadouble - my ex and I split up when DS was 2 (he's now nearly 5). It wasn't rebound, the split had been a long time coming, I already new DP before we split but, whilst nothing ever happened between us whilst I was still married, I had guessed how he felt.
I moved in with my parents after my ex and I split but started seeing DP fairly soon. Then moved in with DP about a year ago. I don't feel we rushed the living together bit, but do wish I had lived on my own with ds for a while - I went from always having my mum's opinion on my parenting, to now always having DPs!
DS' real dad sees him quite a lot (every other w/end and 1 night in the week. They have a much better relationship now than they did when we were together. Ex spoils DS to bits which is a whole other issue as he comes back after a weekend with daddy and I can't do a thing with him as he gets all his own way there and goes to bed whenever he likes etc! He ADORES his dad which is great and how I feel it should be.
My ex didn't want to split up and would prefer we were still together for an easy life I think. He has a new partner now which helps and as also pleased DP! I think life with DP would be better if my ex wasn't as involved but I feel it is obviously far better for DS to have him around.
As far as Laura's comment on opinions of those I trust, that's the scariest bit. My sister says it is clear that DP is jealous of DS from the way he acts, and my mum says DP 'watches' me interacting with DS all the time. I know he is terribly jealous but what can I do? He is bitter because DS isn't his son, becuase I have a past that doesn't include him - which is why I think he'd feel better if my ex wasn't involved, he could at least then pretend ds is his son.
Will getting married and having our own child solve this? He is a lovely lovely man and, for all I've said here, tries so hard to make things work. He just can't understand the love I have for DS.
Sorry it's so long!