I can fully understand this situation - from both sides.
As a parent of three daughters, I can tell you that no man wil ever be good enough for you in your parents' eyes - that's a fact. What parents then do is accept their daughter's choice, make her partner welcome, and keep their mouths shut! Why? Because the potential alternative is a 'choice' situation - and they risk loosing their daughter and grandson because they are too controlling.
I speak from your experience - when I met my girlfriend, she was separated, with two daughters aged sic and four. My mum gave me miles of earache about 'another man's children' etc. Result - my girlfiend and I have been together for twenty-seven eyars, married for twenty-one of them, and we now have three daughters, all adults, and we are fine. My mother and i ahd no contact for sic years, I did not invite her to our wedding, and even now, thigs are seriously strained, and unliely ever to be repaired.
OK - for your situation -
Have a nice calm chat with your folks. Explain that you now their hostility is rooted in concern for you and your son, but that you are an adult and you can and will make your own choices. They can respect your choices as an adult, and be mature and civil about it, or they can risk you not seeing them until they accept your fundamental right as a grown woman to live your own life, with or without their approval, which you would like, but you don't actually need.
Appearences are meaningless. My eldest daugher's partner appeared in her life as a mechanic, with two earings, a baseball cap, and a propensity to drink our beer supplies. We had your parents' concern for our daughter, and her daughter as well, but kept quiet, and waited to see how things went. Now, they have an adorable little boy, our grand-daughter worhsips hm, he has bought the business that employed him, and if i had a son of my own, I would wish for him to be