"I'm going to see what his adoptive birth certificate says. Is this where it would say that he is adopted?"
No, it will not say "adopted" on the birth certificate. Adoptees are given "amended" birth certificates that look the same as "non amended" birth certificates. My birth certificate lists my aparents as my parents. The only "clue" that it is an "amended" certificate is the "I HEREBY CERTIFY" date at the bottom. The certification date is two and a half years after my birth, and a couple weeks after the adoption was finalized. So look at the date on the bottom ~ that may give you a clue whether the certificate is "amended".
Whatever you decide to do, please be careful. You're right, it might compromise your new relationship.
Best of Luck!
