@Casant,
If this were a grammar question or a logic question, I'd say it's either meaningless or inappropriate use.
The long and short of it is this:
Unconditional means ...without limitations.
So, if I were you, I'd be happy that he's says romantic things to you...but understand that such words are without substance - especially with both of you also still in other relationships.
Words mean little without being backed up with actions--which have real meaning. The reality is that both of you get out of those bad relationships and clear up your baggage. Then you can start listening and watching the meaningful actions.