Tired of JNMIL third wheeling after having a baby

I have been with my husband for nearly 3 years. We come from different cultural backgrounds and live in a 3rd country where our only relative is JNMIL who lives in the same building.
JNMIL is a very strong dominant personality who speaks with author and constantly tells me how things are done in their culture, completely dismissing my own culture and traditions. Ive always got the sense that she feels I cant take good care of my husband as Im not from their culture.
She has no husband or other kids and no hobbies or any sort of life outside of work. Shes usually very nice to me but treats my husband as her emotional husband. My husband goes to see her every evening. He works long hours and comes home late so him going there has meant that I never really got the chance to build a home/routine/life with him because so little time is left for us. Shes constantly texting and calling him, buying him clothes, cooking his favourite food, wanting to be involved in everything and needing him for emotional support and company. Im a private introverted person who values space, privacy and boundaries so Over the years my resentment has slowly built up and since having a baby Ive reached the point where even the thought of her makes me want to explode. I feel like Im suffocating because theres always this third person who knows all about our life and constantly uses my husband as her emotional husband leaving me feel like a second wife or a concubine. Ideally Id like to live away from her but its not possible at the moment. Before I had my baby I was worried she would start acting like a mother to my baby so I created very strong boundaries and limited her visists/involvement with the baby. This has worked but unfortunately now shes even more involved with my husband as Im busy with the baby. Shes even said she considered herself and him as “the family”. I am so fed up and perhaps hormonal that Ive gone LC/NC with her and just stopped making an effort with her despite my husband wanting me to be her friend. Am I overreacting due to all these hormones or is this the way to go? I dont know but I just want to create a family thats me my husband and our child, not me my husband child and JNMIL or just me and my child whilst JNMIL acts like a wife to my husband

EDIT: I have told my husband how I feel but hes struggling to see the dynamics as theres some very strong enmeshment going on in his family and he feels sorry for JNMIL as she is alone. He feels its his duty to include her. He doesnt see JNMIL as interfering he just thinks shes being helpful and supportive.. They come from a collectivist culture and DILs usually live with MILS. They rarely marry outside of their culture and were worried I would take their son away and not be family orientated but my husband managed to convince them Im not like that. This makes it so hard for me to address this problem. JNMIL has even told me shes trying to show me what a family is like in her country as if I dont come from a close, loving family myself. My attempts to put boundaries and trying to create a family unit of just me LO and husband is seen as controlling and me taking husband away from them, proving the stereotypes and fears they have about my Western culture and race are correct

Tired of JNMIL third wheeling after having a baby