How does divorce impact children who are 1.5 - 2 yrs old ? Is it better to wait until the child is 2 yrs old ?

My husband and I have been having a lot of bad fights for several years now and refuses counselling. We have lovely boy. My husband loves him and is good to him. But the 2 of us have bad fights. The baby gets really stressed out during these fights. He has this scared/distrurbed look and cries when we fight. I' ve tried to get him to try counselling .. but he has refused it. So separation is the only choice I have now becoz I dont think things can improve between us. Joint custody is what I have in mind whereby the child spends approx half the week with me and half with him.I am financially independant and so do not need any monetary help from him. If there is anyone who has been thru a divorce or separation when their child(ren) were between the ages of 1.5 to 3 yrs, please share your experiences with me. If you have any advice as to how to go about it such that it has the least negative impact on the child, please do let me know.