My reading of the story of Jonathan and David in the Hebrew Bible (I and 2 Samuel) is that Jonathan seems genuinely in love with David. David, I believe, uses Jonathan. He may have legitimately cared for Jonathan, and when Jonathan dies, it seems that his love for Jonathan comes flowing from him, but David also had a habit of treating people poorly (his wife Michal, for example, his children, etc.).
He raped Bathsheba (not seduced, not had an affair with…summoned her…her consent was not considered, and he later had her husband killed). David was a rapist, a murderer, a bad parent, and a cold husband to his first wife (whom he married for a position). Was his “friendship” with Jonathan for a position (at least initially)? What is clear to me is that Jonathan and David were both bisexual and Jonathan was deeply in love with David.
David did keep his (marriage-type) vow to Jonathan and took his son in later in life. Were they lovers? I’d say that part is pretty clear. Were they in love? I believe one was, the other was too shifty to know for sure.
