I think you should not give 人情, and don't go to the wedding party. You can tell your brother you are very busy on their wedding day and not in Hong Kong.
但係我阿哥明年結婚....佢話如果我咁做會"唔好意思" is your brother "唔好意思" or they will "唔好意思" ??
If the former, tell your brother that you 2 are separate gar mar !! If the couple considered your brother & you are 一家人 (are you and your brother 都未婚 now?), they shouldn't have given you the invitation card !!! If your brother is going and you are not, you may ask him to count you in when giving the 人情 lor (but no need to pay more bor). Otherwise, just send a card to their home and congratulate them 算啦 !
同埋怕下個月另一個朋友結婚.我又去飲見到就唔多好喎! This is irrelevant !
Please do not quote any information posted by fungwongphie. 不誠實使用電腦會構成罪行,切勿以身試法。 何謂不誠實使用電腦??