I'm not sure how it works everywhere else in the world, but 99% of U.S. banks and credit unions won't even consider giving a personal loan to someone unless they're already employed and have held the job for at least six months. After all, they want to be assured that they'll be paid back. A loan isn't free money. It's indebted money.
Majority of the time, you also need a good credit score to take out a loan, or at least decent credit. Bad credit or simply not having credit at all leaves you with very few options. Third-party money loaning companies that claim they'll accept any credit score are often sketchy, making use of small print and underhanded methods to take advantage of the desperate. Getting involved with that could potentially lead you to a much worse place.
You're also assuming that environment is the only issue. In plenty of cases, I'm sure it is a factor. However, that can't be said for everyone. Changing the scenery's not going to make a bit of difference to those with serious mental disorders. There are some problems that you can't physically remove yourself from, believe it or not. Your solution of taking a loan and moving far away is not as simple or accessible as you make it out to be, nor as much of a panacea as you think it to be.
It's clear that you don't understand the complexity of many people's situations. You keep bringing up futures and things to live for, but a lot of the time, people are driven to suicide because they're already thinking about the future. In their eyes, they don't see a very bright one ahead of them. Without being in their shoes or understanding their specific struggles, you can't really tell them otherwise. Please try to understand at least that much.
I'd also like to point out a statistical inaccuracy here. Suicide is far from exclusive to or even predominant in teens. Sharing your opinion is fine, but at least have an informed one.
In 2013, the highest suicide rate (19.1) was among people 45 to 64 years old. The second highest rate (18.6) occurred in those 85 years and older. Younger groups have had consistently lower suicide rates than middle-aged and older adults.
I've already shared my thoughts on the morality of suicide recently. Unfortunately, that was on an @allan_selberg thread that has since been deleted. I don't feel like retyping it, but from my response to Zyvox, I'm sure you can figure out where I stand.