The engagement ring is a gift to the person who receives in anticipation of marriage. Therefore, it is traditionally believed that if the person giving the ring breaks te wngahement. The person receiving the ring will keep it. If the person receiving the ring breaks it off, the ring is returned.
My response is based solely on the limited information contained in the question. It is not meant to substitute your attorney's advice.
In PA, an engagement ring is a conditional gift given in contemplation of marriage. If the condition does not occur and there is no marriage the ring should be returned to the purchaser.