I’m not sure what you mean by a “full Mass.” There is no such thing as a “partial Mass.” In Catholic weddings, there is a choice of having a nuptial liturgy alone, or having a nuptial liturgy with a Mass. In shorthand, the option to include a Mass within a nuptial liturgy is called a “nuptial Mass.”
As for the choice of whether the bride and groom have a nuptial liturgy outside Mass or a nuptial Mass, the choice should not depend on the religious affiliation of the groom’s family but on the religious affiliation of the groom. If the bride and groom are both Catholic, it is most fitting for them to be married during a nuptial Mass and for the groom’s family to respect a Catholic couple’s desire for a Mass to celebrate their marriage (and to refrain from presenting themselves for Communion). If the groom is not Catholic, then it is more considerate to him for his Catholic bride to forgo the nuptial Mass so that her groom will not have to be excluded from receiving Communion at his own wedding. If the bride wants to receive Communion in conjunction with her wedding, she, her groom, and her family can attend Mass either the day before or the day following the wedding (or, depending on the timing of the wedding, the morning of the nuptial liturgy).
