Is there an end to the suffering in general?

From a Theravadin point of view, the cessation of suffering is caused by insight, which consists of psychological knowledge about the cause of a specific form of suffering. It is important to bear in mind that the Buddha was addressing the suffering experienced by monks and nuns. His main advice was to set aside greed, hatred, and illusion (of self or god) and get on with the practice of meditation. The Buddha did not deal with the kind of suffering (depression, serious problems with relationships, low self-esteem, inability to find love, etc.) that is caused by physical, emotional, and/or sexual abuse during childhood. Modern psychology is needed to address such problems. Absolute truth does not provide psychological insight (which is a form of relative truth). Not all suffering, such as the loss of child, is caused by lack of insight. If a person feels no suffering, then he is indifferent to the suffering of others. The advice of the Buddha remains valid: Get on with one's meditation in order to deal with one's own lack of insight.

In the Theravadin teachings, the concept of anatta is entirely in the realm of relative truth in the sense that it points out the fact there does not exist an uncaused self. In Mahayana Buddhist teachings, anatta is the experience of sunyata (emptiness), which is a real experience but it does not "convert" suffering into blessings. The concept of Nirvana is a Theravadin concept that has no equivalent in Mahayana Buddhism. The experience of sunyata brings absolute knowledge but not Nirvana. Theravadin insight is relative knowledge about the causes of suffering and thereby provides a means of dealing with and ending suffering. The experience of sunyata does not bring insight, which is strictly relative truth. Both doctors and the Buddha help in real things, obviously. Where did I say the Buddha was "metaphorical"? I invite objective criticism, but not stupid sarcasm.

A disjointed answer:

• This question sounds like it's central to Mahayana (so to answer it you might want to read Mahayana literature, learn from a Mahayana teacher or school).
• I'm not sure that everyone is suffering, in the way that you or I might understand "suffering": I mean, for example, that I didn't get far in explaining the four noble truths to my Mum -- see How to explain what Buddhism is? (and the answer I accepted to that question).
• If you are suffering from karuna ("I feel distress for others"), you might want to address that -- more equanimity, perhaps, or less conceit (the conceit that "I" could help someone).
• There's what can be inferred from the tenth of the Ten Bulls. One of the (English-language) commentaries to that ends with, "... and everyone I look upon becomes enlightened."
• "Envisaging an end to suffering" is also maybe a part of "pure land" doctrines.

A possible hint to the answer comes from the Buddha in MN26:

"Then the thought occurred to me, 'This Dhamma that I have attained is deep, hard to see, hard to realize, peaceful, refined, beyond the scope of conjecture, subtle, to-be-experienced by the wise. But this generation delights in attachment, is excited by attachment, enjoys attachment. For a generation delighting in attachment, excited by attachment, enjoying attachment, this/that conditionality & dependent co-arising are hard to see. This state, too, is hard to see: the resolution of all fabrications, the relinquishment of all acquisitions, the ending of craving; dispassion; cessation; Unbinding. And if I were to teach the Dhamma and others would not understand me, that would be tiresome for me, troublesome for me.'

Almost all sentient beings are here because they want to be here and they thoroughly enjoy attachment, eventhough none of it is permanent and none of it is permanently satisfactory. Even if they suffer much (for e.g. in hell), they continue to cling to their selfhood and maintain their craving to-be, not ready to let go.

If you look deep into yourself and find that you're not ready to let go of your selfhood and not ready to let go of your craving to-be, then you could empathize that this is indeed the case for the googolplex of beings out there.

Even if you had the power to end all sufferings, I bet there would be great opposition to that, from the vast majority of beings who are not yet ready to let go.

MN75 provides a reason why sentient beings see "painful" sensual pleasures with a biased perception of being "pleasant":

"Now suppose that there was a leper covered with sores & infections, devoured by worms, picking the scabs off the openings of his wounds with his nails, cauterizing his body over a pit of glowing embers. The more he cauterized his body over the pit of glowing embers, the more disgusting, foul-smelling, & putrid the openings of his wounds would become, and yet he would feel a modicum of enjoyment & satisfaction because of the itchiness of his wounds. In the same way, beings not free from passion for sensual pleasures — devoured by sensual craving, burning with sensual fever — indulge in sensual pleasures. The more they indulge in sensual pleasures, the more their sensual craving increases and the more they burn with sensual fever, and yet they feel a modicum of enjoyment & satisfaction dependent on the five strings of sensuality.

For the multitude of sentient beings who want to-be, the best thing that you can wish for them, comes from the Karaniya Metta Sutta:

Think: Happy, at rest,
may all beings be happy at heart.
Whatever beings there may be,
weak or strong,
without exception,
long, large,
middling, short,
subtle, blatant,
seen & unseen,
near & far,
born & seeking birth:
May all beings be happy at heart.

No. But for your world, as you perceive it, with all it's and you relatives, this very wandering on can/could find an end.

Anamatagga-samyutta — The unimaginable beginnings of samsara

Yes and no. To be is to suffer. Our desire to be is what keeps us on the round of rebirth. Nibbana will come to every being just not all at the same time(Vast time). That's what I've heard from various teachers.

We mix our individual truth up with the truth of society and until we can see the difference we have no business trying to fix society as we seek while ourselves we are broken. Our business is to fix ourselves then fix society one individual at a time. The society of the entire universe.

So, imho, I think you should tend to the universe of mind and body, moment by moment instead of the "business as usual", blurry truth of the world.

The ultimate truth is that there is no suffering, absolutely for all, for ever. Everything is already Nibanna.

However, the mundane truth is that there is suffering, absolutely for all, for ever. Everything is Samsara.

Can you change Samsara to Nibanna?

That would be impossible. How can you change Samsara to Nibanna, if Samsara is already Nibanna? It's impossible.

Can you change Nibanna to Samsara?

That would be impossible. How can you change Nibanna to Samsara, if Nibanna is already Samsara? It's impossible.

An instructed mind, very well versed in the Dhamma, knows: this is change, this is its cessation, and this is its end. Knowing change in this way, he let's go of change. His craving ceases and right discernment arises: From ignorance as a condition comes craving. From craving as a condition comes change. From change as a condition comes suffering.

Thus knowing, an instructed mind, very well versed in the Dhamma, gives up change. Giving up change, suffering ceases, absolutely for all, for ever.