The person who cares too much for others and values others' happiness before his own happiness gets hurt usually. These kind of people are taken for granted by other people as they always agree to others or try to keep others happy. They never care for their own happiness and are selfless. But as a result other persons cannot see their value and start ignoring them. So they become the loneliest inspite of being selfless.
True. The person who always tries to keep every individual around him/her happy is lonely and unhappy himself/ herself.