When do you realise and give up ?

You are 32-34. Every single friend around you has gotten married and is doing well professionally. Friends no longer have time for you. Friends meet other friends with their families. You are confined to your own little world with no friends. All of a sudden you realise, you are one of those people who are not blessed with the joys of Career progression and marriage. People don't value you. Your existence holds no value to others. When do you realise this and when do you give up on your dreams ?