First, discuss your feelings frankly with him. Ask him why he chose not to take you to the wedding. Some men may choose to participate in family activities without a partner because they are nervous, shy or introverted. Others may have some specific concerns, such as the size of the wedding, or feel uneasy about your integration.
Secondly, after knowing his specific thoughts, you need to seriously consider whether this relationship is worthwhile for you. If his family doesn't know about your relationship, or he doesn't intend to share your relationship with his family, then you may need to reconsider your relationship.
In addition, if your boyfriend doesn't take you to his wedding, it means that he is not ready to let his family know about you or your relationship. In this case, you may need to know more about his views on your relationship and his views on sharing your relationship with your family.
Finally, if you think he should not ignore your feelings like this, then you can consider breaking up with him. If you think this is unacceptable, then you may need to reconsider whether this relationship is really suitable for you.
In short, whether you decide to continue this relationship or not, you need to seriously consider your feelings and needs. If you feel unhappy or uneasy, then you should seek help or advice to better deal with your emotions and problems.