If she is a Catholic, and deliberately marries outside the Church, she will not be able to receive the Eucharist; it is a grave sin.
She needs to have her marriage blessed by the Church; She [the Church] cannot recognize a marriage outside the Church for a host of reasons, especially because that marriage is not a sacrament, and sacraments, like Marriage, are for the Church, not for the Justice of the Peace.
She should meet with a priest and discuss this further. If she is marrying someone who has complications, like having been married and having no annulment, there are issues to work out.
People tend to run away from the Church when they imagine obstacles, but the irony is that tackling those obstacles, may provide the safest and freest way forward.