How do I tell my family?

Hey guys! I just found this group & I am so excited I did 🙌🏼 I am 23 & my boyfriend will be 48 in a few months. We have been together for almost a year even though neither of us expected our relationship to turn into a serious one. Because I didn’t expect it to become serious, I’ve never realllly told my parents the full story about us & they currently think I am single. I have NO idea how to tell them without it turning into a huge blowout & I really respect my parents & my relationship so I don’t want to keep them in the dark any longer. How did you guys tell your families & were they accepting?