I'm looking at "belief" as something that is required when there is no evidence. Where there is evidence you don't need "belief" in the strictest sense of that term.
So, you separate "what I believe" from "what I have faith in". I don't: I use the word
believe according its common meaning and add "in" when speaking of a principle or concept. (as : "I believe in equality under the law" in theory, even though it's far from a reality in application.)
The amount of evidence available for a new datum varies greatly from case to case. In general, I'm inclined to believe reputable scientists, even if I don't understand everything they do, and even if they don't lay all of their ten+ years' of research before me.
I tend to believe a few people I know well, who have been truthful in the past. I tend to believe, at face value, anything anyone tells me about their own feelings.
If I were on a jury, I would be inclined to acquit or convict on a preponderance of evidence, beyond reasonable doubt - rather than beyond a shadow of doubt - partly based on my own impression of witnesses' credibility and competence - much of which is never in evidence.
Regarding honor, fidelity, love, etc. Those are feelings, moral constructs and it's all relative.
Fidelity is not an emotion; it is a pattern of behaviour. Honour is not an emotion; it is a character trait. These are long-standing tenets of relationships in any culture. Your culture may value some ideals, behaviours and relationships more than they value others, but the individual can choose to disbelieve in the values of their own culture, or prefer a principle from another culture, depending on your their proclivities and experience.
For example, I believe in the reality of love - as a central experience of sentient beings, as a basis of relationships between individual sentient beings, and I do not believe anyone should have the power to restrict or control another individual's freedom to love.
Slavery used to be part of our culture.
And many other cultures through history, and some cultures today. Yet some people, in each of those cultures utterly rejected and do now reject the practice, because they
do not believed in it; they do not believe any individual should have the power to subjugate another.
There is nothing to "believe" in regarding slavery.
Of course there is. Some people held it as an article of faith that 'superior' races or civilizations had t
he right (god-given or natural) to enslave 'inferior' peoples. Some people today hold it as self-evident that debt-slavery is just and proper.
Others believe that all slavery - including coercion through economic dominance - is wrong.