Yes, it is easy to advise people to follow the wisdom of Gita

Yes, it is easy to advise people to follow the wisdom of Gita and it is indeed that Gita says that it is extremely difficult and almost impossible to follow the preachings of Gita and attain Salvation. Gita says only a small percentage of people every try seriously to follow the path of Yoga taught in Gita and of them hardly a few succeeds to achive Salvation: most people give up somewhere along the line.  The feeling of being cheated arises from ego and unsatisfied desire.  That the heart is adament in craving for self-respect and dignity is also due to the existence of ego and desire for respect and dignity. These are the impediments to proceed on the path of Yoga to salvation and practice of Yoga is essentially to get rid of all desires material or otherwise like self-respect or dignity. That is what Gita says. Who is son and who is parent: all such relationships that results in hearts craving for receiving or expecting some specific kind of behavior from sons or others are relationships of illusion. Gita urges one to get out of this illusion and remove all expectations based on one's actions or relationship.
What do you do? Either you continue practising the principles of Gita or you do not. Gita says the only way to get the pains of disappintment and suffering is to (a) give up ego, (b) give up all desires and expectations, (c) practice equinimity (seeing God in everything including the enemy and the worthless sons, and (d) submit completeltly to God where or not He brings any relief to you in the Worldly life. If I cannot do that, I have to find out an alternative solution to my probles of disaapointment and suffering. At an old age if it is poosible to get a suitable alternative, one can try that.  and if that effort fails, one has to accept whatever happens. There are two ways of accepting: one is to cry and repent and blame the society and others and the second one is to submit all problems and sufferings  to God as a small child does to the Mother and concentrate all thoughts on the worship of God. One has no other option. Whether Gita says this or not is immaterial. If one wishes to remain as a slave to the illusion or the cravings of the heart or widow's crying, God is not going to complain..