I came out to my boyfriend almost a year after we started talking. He took it really well and came out as bi a few months later. He has yet to tell his family but he loves me and calls me by my name and pronouns, etr. It took a little getting used to, but he's really good at it now. Best advice is to be open and honest with your partner, you'll be better off for it. Keeping things from them only stresses your relationship rather than protecting you. I was open throughout my process of questioning my gender and my boyfriend constantly reminded me that he loved me not for my gender but for who I was as a person. You are so much more than just a gender, and when you come out as trans that doesn't (and shouldn't) change anything, you are still the same person just by a different name and pronouns, and you still have all that love that you had before you came out or transitioned :) good luck to ya!