Everything you said above is valid. And now, we need to work on the solutions.
Very few people meet someone, shake hands, get married, and then have sex and make babies... in an hour, a day, or weeks or even months... well, sometimes people just go from meeting and making babies in the same evening... but that's not generally a preferred option...
So, your first question:
How does one earn trust, once it's lost?
That's a huge question. Especially the last part.
Do you trust someone the moment you meet them?
What does it take to trust someone in the first place?
How do you KNOW they are being open and honest?
Does it really matter if they're completely open and honest, if all you are doing is buying batteries from them?
What we are talking about here is an M, which includes intimacy. Intimacy generally requires trust and openness and honesty. At least, to an extent.
What are you holding on to... that makes you not want to trust your H?
How can your H earn your trust?
Start small...
Ask him to take out the garbage. If he does so, will you trust him? What if you ask him a second time and he doesn't. Does that prove he cannot be trusted?
Trust is not just earned by being open and honest. It is earned through CONSISTENCY. And it's not just about the BIG things... it's about the little things, too. Because they "add up".
You will read on this site often, that this isn't a game of keeping score. Unfortunately, it is human nature to keep score...
If someone keeps lying to us, in one form or another, over and over and over again... well... continuing to trust them might be a form of insanity...