I don’t like to decide what is normal. If you tend to be a person who does not easily trust then to be un-trusting is normal for you.
Now you’ve got a difficult chart and I think this is reflected in your relationship. Because you are having great sex with a man who is sweet and understanding yet you are suffering and this is the thing to investigate and try to alter. Judging from what you’ve written he’s done nothing to betray your trust or arouse your suspicion so where is this coming from?
You don’t have the chart of someone who is particularly paranoid but you do have the chart of someone with a high sex drive, probably interested in psychology, prone to worrying and get this: fantasizing.
And I don’t KNOW but if I was going to guess… considering his planets are opposite yours I would imagine it possible you have his motivation confused with your own. You are a born investigator see. So are you in the relationship for love… or something else?
And I am not judging this so don’t take it that way. What I am suggesting is that you are a very complex young woman so just keep asking questions like this one and you’re going to be fine.