But obviously, when I got married, my friend was taking an exam and didn't have a chance to come to my wedding, so I'm sorry, even if I wanted to reimburse her for her travel expenses, she couldn't come. But judging from the situation of many young people getting married now, it seems that all students come to the wedding at their own expense. After all, the young couple spent all their money on the wedding when they got married, so there is still so much money to pay for their friends. If friends think that the round-trip fare and missed work can't get bonuses, then naturally they can choose not to attend the wedding. That depends on whether this friend values money more than the friendship between you.
Friends can come or not, that's their freedom, but relatives must come. For your biological parents, you may not need to spend money at all. Now the children at home are not treasures in the eyes of their parents. How can they be willing to let you spend money? Parents spend money on such a happy event as marriage. Of course, if your parents-in-law have poor family conditions, it is reasonable to take the initiative to help them reimburse the round-trip fare.