How can I trust doctors?

Throughout my entire process since the very beginning, I have had a hard time trusting my dentist and knowing what is the best decision. When it comes to dental work, treatment gets expensive very quickly and there's not much insurance coverage for it either.
I decided to post about this concept of trusting your doctor and knowing that they are telling the truth. It's really difficult when you want to make the right decisions for your health, and you have to put complete trust in someone you barely know who is making a living off of your problems. I'm not assuming that all doctors want to take your money, regardless of whether you actually need the treatment. I'm simply posing the question, how do we find a doctor we can trust?
Understandably, we go to multiple doctors and seek out multiple opinions. In some cases this can become more confusing. Is the doctor just saying what we want to hear? Are they just giving us an alternative to gain our business? It's a sad thought, but it's something that I think goes through every patient's mind when they are faced with serious medical concerns that are about to cost them a ton of money.
I wish there was some easy answer. I am trying to get through my treatment, but the further I get into it, the further I have to go. Recently I was told, after having an orthotic for my jaw for over a year, that I would now need another orthotic. My consultation made sense, it was understandable and I feel like I can make an educated decision, but how do I know for sure?
My specific case is unique to me, it's not something I can just search for on the internet and find all the answers. Some people decide to go the surgery route. I decided not to, and I'm still happy with that decision. Yet, it is still difficult to put my trust in a dentist and know for certain that they have my best interests at heart.
The previous orthodontist I went to wanted me to go through multiple surgeries, fly to California for the treatment, have an orthotic, braces, etc. I'm glad I didn't go with anything that permanent, but did she really believe she had my best interest at heart? Was that simply the only treatment options she was familiar with and believed to be the best?
I think what is even more difficult perhaps than justifying it to yourself, is justifying it to family. Especially in the case of TMJ when you can't show them your pain, and you can't prove that this is necessary for your own comfort. I've come a long way, and in some cases you have to even justify why you are still going through with this, and why you're worth the cost of treatment.
It's not just having to wear an orthotic, there's also the emotional stress of making these life-changing decisions, being self-conscious, and the lingering problem that you are constantly waiting to be resolved.
I mentioned in a previous post how my orthotic had broken and a few more pieces had come off. I started getting terrible neck pain that I just started to get used to and assumed was just due to stress. At my last visit, my dentist was able to patch up my orthotic so that it no longer was missing the piece. Within a day I woke up with all my neck pain gone! I couldn't believe how quickly it was gone, and I realized that it wasn't just something I had to deal with, it was real and it was further validation for having gone through this whole orthotic process.
Anyway, in the end, we do the best we can with the information we have. It helps to have some people on your side, but it also helps to have some people not on your side so you can really question the decisions you are making and stay objective throughout the process.