Hi Student,
As a student of academic psychology, I have learnt that our thoughts can influence our feelings, but our feelings can also influence our thoughts. If I am correct, Buddhism more or less explains things in much the same way too. In paticca samuppada (something like a cause-effect cycle, expounded by the Buddha), sankhara (which are thoughts and volitions) paccaya (give rise to under suitable conditions) vedana (which are feelings) through other links, and vedana can also paccaya sankhara through the same links in reverse order.
While Lal has given you some food for thought in a general sense and from a different perspective, Akvan seems to have approached your problem from the forward order of sankhara paccaya vedana (anicca and dukkha sanna) , while Tobias and y not seem to have suggested approaching your problem from either the forward order of sankhara paccaya vedana or the reverse order of vedana paccaya sankhara (I cannot tell which order metta bhavana falls under).
As for me, I will also try to help you with some ideas of my own (with help from Lal and The Buddha).
Think back to the times when your parents had shown their care and concern for you, even if in only small gestures or words. Surely there must have been times when you were touched by them? I would like you to reignite those memories and loving thoughts for your parents again and bring them to the forefront of your mind. You will need to suppress hateful thoughts with love. Once you have recalled those times, keep them in your memory and heart. Then think back to those times you might have got into an argument with your parents because you thought that they were incapable of understanding you. In the post ‘Kammattana (Recitations) for the Sotapanna Stage’, under #12, it is written ‘…If one had (even inadvertently) done a bad deed to someone that day, one could be thinking about that person and ask for forgiveness. This is a very effective way to calm the mind and reduce tensions… If done sincerely, one should be able to see the effects in real life. You may notice that the tensions with that person automatically reduced… What happens is that those strong javana citta that you generate can produce cittaja rupa that can affect that person even over long distances’.
Before you finally conclude that your parents are incapable of understanding you, perhaps have you examined any role that you may have had to play in this? For example, have you refused to let them into your world because you thought that they could not understand you? But if you do this, how can they even enter your world to understand you better? It is important to examine these things objectively and non-judgmentally, and not to let defensiveness and other negative emotions get in the way of an honest assessment, if you would like to see things more clearly as they are in reality.
I think the Buddha said that hatred cannot be conquered with hatred, but must be conquered with love. This can apply to non-enemies like family members you may feel friction with too. The Buddha also may have said that one solution to ease such hostile feelings is to give a gift to the other person(s) one is having problems with.
This gift could be a material gift or it could be in the form of a friendly and sincere help such as making coffee for them. Engage the othe person(s) in the gift-giving too. Ask them to reciprocate if they are willing to. If so, you will be able to experience the effects of gift-giving from both the perspective of the giver as well as the receiver.
What were your thoughts when you were giving the gifts? How did you feel after giving the gifts? How did you feel when you received any gifts? What thoughts did these feelings trigger in you? Ideally this internal reflection will activate both the forward and reverse processes of sankhara paccaya vedana as well as vedana paccaya sankhara. The combined results of both processes could be very strong, not to mention the myriad other effects this could spin off. For paticca samuppada is complex, and the more links there are, the more varied and possibly stronger the effects can be. Engage in performing helpful services or giving material gifts every day if possible. You may be amazed at the results one day.
One more thing: I think the merits of giving gifts depends on the receiver as well. Not many are more qualified to receive gifts to than our parents, who have enabled us to attain a human body which is an extremely hard result to obtain. Therefore, if I am not wrong, sincere gifts offered to our parents without any ulterior motives, while knowing that such acts will bear good fruits, are highly meritorious indeed.
Do let me know if you have engaged in any of the tips I have suggested, and if they have been effective over a period of time. I sincerely wish you all the best! :)