I am invited to a Catholic wedding of a relative who is living together with his fiance prior to marriage. Does my attendance aid in scandal? I assume that they are having a nuptial mass.
Once the couple is married they will no longer be “living in sin” so the wedding sounds like a good thing to me and I don’t see any danger of scandal in attending. Hopefully the couple will approach the sacrament of penance prior to the wedding to better prepare them to “receive the sacrament of marriage fruitfully” (cf. Code of Canon Law, 1065.2).