I (40F) struggling with resentment buildup and boundary issues with SO (42M)

I (40f) have come to this sub to seek advice around resentment and boundary issues with SO (42m). My SO over the last 6 months or so has become incredibly hyper focused on business and creating relationships everywhere he goes. His main goal in life is wealth. Primarily, our bookkeeper has been top of mind for him. It’s like NRE. They communicate about more than just business and bookkeeping. They will text, FaceTime, and phone each other in and outside of working hours. I don’t have any thoughts that my SO may be cheating, I like these people also. I would like to be closer with them and her especially. It feels more like a competition to me. I feel I’m competing against my own husband and her. Feels awful. They discuss everything together and my SO goes to her for difficult decisions and then will bring back to me after with the decision essentially made. This leaves me feeling unimportant and left out when he feels the need to go to her before discussing things with me. I experience horrible bouts of imposter syndrome. When we get together with her and her SO, it’s like my SO and her are the only ones communicating because they don’t actually give me or her SO a chance to speak really without it feeling like we’re interrupting. I feel so low. My SO tells me he misses his happy wife. He even told me I have resting bitch face. I don’t feel this way. Maybe I’m just tired and maybe resting bitch face is ok. Or is it?

My question to you is:

Ia it appropriate for my SO and our bookkeeper to have such a tight relationship?

Is it ok for my SO to dictate how I should feel and how my face should look? And when I should be happy or smile

I literally feel lost in my relationship. He has changed so much that I hardly know who he is anymore. He has told me that he does not need to change anything that he’s doing because it’s not wrong. He said if I made x y z changes, our relationship world be fixed.

EDIT: the individual my SO is communicating with is not an employee of ours, she is external bookkeeper.