Why don't you ask him what's up with it all? Just sit him down and calmly describe the things that are bothering you and ask him to explain to you his thoughts and feelings on those behaviors. You may find there is something going on there between him and your son that you're not aware of. Or it might just be the kind of relationship they've developed and are fine with.
I always wanted a guy who would be willing to adopt my kids, to act as a father to them. And I've been very fortunate to have found that, and that my sons fully accept him that way. But, I also always knew that I couldn't force them to have the relationship I wanted them to have. They had to feel their way and figure out what they wanted between the three of them, and I had to simply step back and let that happen.
If they had not developed this kind of relationship, yes, I probably would have been somewhat hurt by that. But at the same time, it is their relationship. My romantic relationship with him is separate from their relationship with him. If they all feel comfortable with a buddy/buddy kind of relationship, or a civil "We live in the same house and we all love Mom, so we'll be polite and nice to each other but that's it" kind of relationship, then that's what they should have, since it's what will be most natural and work best for them.
Talk to him. Talk to your son. Separately. If they're both happy with the way things are, then as much as you might want things to be different, you need to let go and leave it alone.
I always wanted a guy who would be willing to adopt my kids, to act as a father to them. And I've been very fortunate to have found that, and that my sons fully accept him that way. But, I also always knew that I couldn't force them to have the relationship I wanted them to have. They had to feel their way and figure out what they wanted between the three of them, and I had to simply step back and let that happen.
If they had not developed this kind of relationship, yes, I probably would have been somewhat hurt by that. But at the same time, it is their relationship. My romantic relationship with him is separate from their relationship with him. If they all feel comfortable with a buddy/buddy kind of relationship, or a civil "We live in the same house and we all love Mom, so we'll be polite and nice to each other but that's it" kind of relationship, then that's what they should have, since it's what will be most natural and work best for them.
Talk to him. Talk to your son. Separately. If they're both happy with the way things are, then as much as you might want things to be different, you need to let go and leave it alone.