Welcome to MarriageBuilders, Tim...
Have you been reading all the articles offered here? The links are to the right of your screen...about Love Busters, The Love Bank, Emotional Needs...Radical Honesty?
All of these can help you in your marriage...you shared something with your wife which terrified you to speak of, is that correct? Her reaction is her own...not yours...you didn't cause her to react in the way she did. She just did.
I am looking at your "like she's calling me a liar" because you didn't answer her truthfully when she first asked about your sexual history...well, you lied by omission. Own that you did. Ownership isn't blame...it is knowing your fear and owning it as yours...sexual abuse creates secrets, and speaking truth is very difficult. Own both--you withheld and you spoke. You broke the secret.
Respect her more...continue to share your thoughts, feelings and beliefs...using "I" statements...speak of loving her, trusting her, your desire to grow and be free from secrets from fear. Let go judging whether she is taking something well or not...listen and repeat what she says, which allows for her to confirm or to clarify what she means and validates you heard and understood...
The pain you are experiencing from her reaction is a mirror to what is already in you--when you keep secrets, that tells your self that self is bad, not worthy, valueless. Losing ourselves is as painful as losing our partners...just isn't as evident because we've done it for a really long time.
Marital Counseling would be awesome...might consider calling the Harleys...because this isn't a marriage ender...not beyond repair...and knowing the four rules of marriage and living them can take this event in your life as a benefit to your relationship.
Stay here and read...you're not alone. I had your wife's experience, only it was after 19 years together. Respect, time and patience is part of marriage. Not a deal breaker.
LA