The answer very simply is no. Catholic Sisters and Nuns cannot get married. Here’s why.
When a woman becomes a nun or sister (or a man becomes a monk/brother/friar), she makes 3 vows: a vow of poverty, a vow of obedience, and a vow of celibacy. So just as married people make vows to each other — that they will love one another and be a family for their whole lives, “till death do us part”, so to do sisters make vows to God within the context of her religious community (her family) for her whole life. These are two different kinds of life commitments.
As a married person, your love for God is expressed through love of your spouse and children and through the work that you do. As a sister, your love for God is expressed through your community life with your nuns and through prayer and ministry. There are similarities, but the two life commitments are mutually exclusive.
It is possible, however, for a woman who has been married and is no longer married in the eyes of the Church to become a nun. It is also possible for a woman who was a nun and left the convent validly to get married. But she cannot do both at the same time.