Can you summarize Friends and Flatterers by William Shakespeare?

The poem is a lament by the speaker about fickleness. The speaker, upon an occasion, hears a nightingale sing and takes pity on the poor bird for its beautiful song sounds like a wail. He then expresses the sentiment that the bird's complaint is all in vain, for no one will hear its cry. All of its kind are too occupied in singing their own songs and plants (symbolised by trees), in general, cannot hear it nor can any give it any cheer.
The speaker then states that he could hardly stop himself from crying since the nightingale's grief reminded him of his own sadness. He alludes to Greek mythology by mentioning king Pandion who died of grief on hearing that his daughters had died. The reference suggests that he and the bird are alone in their sadness and pain, for king Pandion's sorrow died with him.
The speaker says that his and the bird's friends are like lead, implying that they are devoid of any feeling or compassion. The speaker continues to bemoan their lot, stating that no one will share their misery. Even Fortune is fickle and they have both been misled since those who have praised them are not around to comfort them.
The speaker states that it is easy to flatter and beguile by using words that mean nothing. Flatterers find easy victims and would do anything to exploit those whom they target, always complimenting them, whilst they do not really mean what they say. He mentions specific examples of how these flatterers can charm others to get an advantage: if the person is a wastrel, they will compare him to a king and help him spend all he has and if he has vices, they will use these to entice and mislead him. If he loves female company, they would provide him with what he needs for the flatterers have women at their beck and call.
The speaker then declares that once the victims of such deceptive characters lose everything, their so-called friends instantly disappear. Only true friends will remain to assist when one needs their help the most. Such friends will share your despair, stay by your side and feel what you feel. The speaker ends off by saying that these actions are those of a genuine friend and will clearly distinguish him or her from the fake ones.