Go with it.
You have the RESPONSIBILITY
to state your needs, wants, and limits.
If there's room for negotiating, you can try to sort it out.
But if there is no happy medium to be had -- best to end if honorably before things go deeper. Everyone needs to know what they are signing up for and AGREE to what they are signing up for.
Being outed by indiscreet people is not the same as just being annoyed by fluffy fb postings.