told that in some patients it can cause suicidal thoughts
So many times the drugs can cause way worse symptoms of the things they are supposed to "cure" (or suppress)
in the US a doctor gives whatever the customer will pay for
Doctors prescribe what the drug companies pay them most to push, and they pay lavishly.
No different to financial advisors suggesting you put your money in mutual funds that pay them the most commission.
Fundamentally, every profession is made of people and people are always the same - selfish and driven by their own gain. If you believe your doctor is some holy saint who's only looking out solely for your best interest, you may need to look closer.
The best case for you is that they happen to get the most or equal kickback from the drug company that happens to make the drug that best suits your condition.