I still think Elaine is in the right. Ale's too emotionally stunted and spiteful at this point to really be an effective Duke. He's just laser focused on that one girl, and I have no doubt he'd let the land rot before letting her go. He's even putting blame on the wrong thing- he's thinking 'oh she's overstressed because of outside pressure' as opposed to 'wow, I'm hanging onto her a bit much, huh?' He literally does not have the emotional maturity to think of anything longterm, it's just 'I want this girl to stay next to me forever and ever and ever and ever' and that's it. Ibelina didn't really help things either- she paid the idea lip service, made the occasional suggestion, but she didn't push the issue- nor could she, really, without likely making him angry, which was bought up and of course dismissed later.
Chances are he'll probably either give her a noble title that she is WOEFULLY underprepared to actually use (I.E. make the actual nobles mad because it'd appear she did nothing of merit to deserve it) or simply force her back no matter what and leech even HARDER onto her. Either way, it's not a good look. I get that Alejandro's had a VERY rough upbringing. However, I don't think that validates him being like this to literally everyone that's not her- it gives a reason, sure, but that doesn't make it right or good. IMO, Alejandro isn't a good person by any means, and honestly? I think that one way or another he WILL cause a war- over Ibelina, most likely. Sounds romantic, but I'm worried about everyone else in the territory, to be frank.
The worst thing about it? I can see no real good outcome here: the country will have either a lame duck Duke that legit does not give a shit about anything or anyone but Ibelina (who'll be stuck by his side forever even in ways she doesn't want, possibly in a gilded cage), or it'll have a war over her. Alejandro's too broken as a person to be a good ruler. At best, he should abdicate his position and just be with her that way- but of course that won't happen because that'd be too simple of a solution in this story.