I understand people getting married wont be able to invite everybody they knows. For financial reason or distance reason. If one of my friend getting married not inviting me, and i know the news i will still sending them a wedding card to congratulate them. Some people making a wedding just as a family affair, they can't afford to have a grand wedding. Some people rather spend the money for putting a down payment for a house which is IMO it is acceptable. I will be still sending a best wishes for them :-)