Agreed, but the issue's a bit more complex than that, I would think.

Are you positive that morals are different for everyone?
Humans by nature are all essentially the same. If you believe that morals are merely a means of keeping a society together, I'll turn around and question how you know that. What are morals? Where do they come from? Who creates them?
And is there any way to empirically support that position, seeing as the position itself comes from a positivist way of thinking?

The question comes up: are there inherent human rights and laws that must be adhered to at all costs?
The laws of our nation are built on such a principle. Modern democracies (republics, technically) are built on the idea that humans have inherent, unalienable rights that cannot be infringed for any reason.

Perhaps these laws are built for the benefit of our society. But if we believe that morals and laws are merely a means to achieve the ends of society, the question arises: is society really necessary? What is so great about society?
What does society produce for us? And might our answer to this question assume something metaphysical about the meaning and goal of life?

Just some food for thought.

Well, I'm glad that you've taken the time to respond. Let me address some of these points individually.
(I like the avatar by the way.)

I was brought up believing that crying and suicide were signs of weakness and that if you did either of the two, it meant that you were inferior.

I'm sorry to hear that. That's what results from cultural ignorance and a failure to question the most basic aspects of human nature.

Emotions are not a sign of weakness. In fact, it is quite the contrary. It takes a very strong individual to openly display their emotions. Society teaches us that hiding our emotions makes us appear stronger, but this is nothing more than a symptom of baseless pride. Pride does not give us strength; it merely blinds us to the reality of how things really are.

The greatest strength is not pride, but humility. Anyone can be proud, but humility takes virtue.
And it takes a great deal of humility to admit your feelings and cry in front of others.

But I've had suicidal thoughts myself

As have I, unfortunately.
But I've come to learn that the true cause of sadness is not in what happens to us, but rather in the way we perceive the things that happen.

When we view humanity in a negative light, we start to think of them as obstacles to our happiness instead of as people who are naturally social and empathetic beings.
When we view humanity in a negative manner and assume that everybody is a burden to us, the rest of the world sees us as someone who hates them, and they tend to view us in the same way.

Take a moment to reflect on the following question: is it the world that needs to change, or our perception of it?

Think about it. We all live in the same world, do we not? Yet some people are happy while others are not.
Sure, some people go through things that others have not. But why are some "lucky" people sad while certain very troubled people remain happy? Are our experiences really the greatest factor in determined how happy we are? After all, a man once said that life is 10% what happens to you and 90% how you react to it.

Obviously, there is an error in perception. Is it the happy people that "just don't get it," and are blissfully unaware of the struggles that the sad people go through? Or is it the sad people who don't get it, and are lost within the dense fog of their own self-destructive perceptions?

I myself would say that it's a little bit of both. Happy people are often unaware of the trouble that other people go through. But more importantly, I think, is the perception of human nature that many people hold without realizing its horrible implications and consequences.

The key to happiness is seeing things as they truly are. Depression is like a fog, a barrier over our eyes that blinds us to the truth.
Life is a gift, and this world is a beautiful place. The true nature of humanity is revealed in the scientifically proven fact that our greatest happiness comes from serving others.

The key to happiness is realizing the truth about the world. The key to happiness is understanding beauty and love. But most of all, the key to happiness is realizing that our desire to love others can sometimes bring us more happiness than our desire to be loved.

Hang in there, and question everything. Sometimes what we undoubtedly call truth is in reality a fallacy that leads us to ruin.

they were actually biological? What if suicidal thoughts or behavior was a fight or flight reflex?

At first it seems reasonable, but this is actually a topic that has been addressed by scientists and has been disproven.
We have discovered that some people might actually inherit genes from their parents that make them more vulnerable to depression.

However, we also have discovered that suicidal tendencies are not inherited and are not related to our physical makeup. Suicidal thoughts are a symptom of depression but they are not guaranteed.

Perhaps we're not so afraid of death as initially perceived.

That raises questions about the nature of death.
Is death a release of our burdens?
Is it an end to our joy?
Or is there something afterwards which gives our life a purpose?

The answer to this question would definitely give us an answer as to whether or not death is something we should even fear in the first place.

*****

Thank you for your comment. You certainly made some very interesting points.