Trust is both and emotional and logical act. Emotionally, it is where you expose your vulnerabilities to people, but believing they will not take advantage of your openness. Logically, it is where you have assessed the probabilities of gain and loss, calculating expected utility based on hard performance data, and concluded that the person in question will behave in a predictable manner. In practice, trust is a bit of both. I trust you because I have experienced your trustworthiness and because I have faith in human nature.
We feel trust. Emotions associated with trust include companionship, friendship, love, agreement, relaxation, comfort.
There are a number of different ways we can define trust. Here are the dimensions of trust and consequent definitions.
It is a normal part of the human condition to be constantly forecasting ahead. We build internal models of the world based both on our experiences and what others tell us, and then use these to guess what will happen next. This allows us to spot and prepare for threats and also make plans to achieve our longer-term goals.
The greatest unpredictability is at 50%; a reliable enemy can be preferable to an unpredictable friend, as at least we know where we are with them.
Trust means being able to predict what other people will do and what situations will occur. If we can surround ourselves with people we trust, then we can create a safe present and an even better future.
if we lose trust its very difficult to gain back
You can save the money for a lawyer. You are not going to keep a greencard if you want to use it as a tourist visa. If you have a greencard you will need to live at least 6 months every year in the US. You also need to maintain a place to live and other obvious ties to the country. Otherwise they could easily decide that you have abandoned your greencard and take it from you.
If you want to come as a tourist, try to get a tourist visa. Much cheaper. If you are from a visa waiver country you don't even need that. You are not allowed to work on a tourist visa, but apparently you don't want to do that.
In order to ask a lawyer meaningful questions you need to tell the lawyer on what basis you want a greencard, the most common types are through close family or through employment.