The kind of relationship you're describing sounds like "I love you only when you do what I want". That's not love - it's a transactional arrangement.
So you're saying Lae'zel approved of every single choice you made for the entire game up until one of the major moments of the ending? Since you say she only loves you when you do what she wants, that must mean you've only ever done things she wanted up until then, yes?
And also that she actually expressed "I fell in love with you and have now fallen out of you"?
If Lae'zel's people matter more to her than I do, that's perfectly fine, but I won't die for her, I won't sacrifice my people for her, and I won't abandon my beliefs for her either. That turns everything into a casual situationship - two self-centered individuals incapable of forging a meaningful bond. It doesn't make a relationship with her interesting or deep - it just makes it indifferent to me.
The fact that you think someone must be willing to sacrifice their people, abandon their beliefs, and even die in order for their love for you to count is genuinely terrifying. I hope you talk through these issues with your therapist and work on developing the ability to view other people as autonomous beings and relationships as complex and diverse.
The space between "casual situationship" and "would literally give up everything I've ever known or cared about and have my happiness and everything else depend entirely on one person" is vast, the latter is generally not healthy for anyone involved, and anyone who feels, thinks, and behaves that way weeks or months into a relationship probably has a lot of deeper issues they need to work out before they can actually be a good partner.
Considering both Lae'zel and Shadowheart are extremely recent cult survivors - so recent, in fact, that you've watched those events unfold - they DO have a lot of issues to work out before they can be good partners, and the last thing they need is some dude demanding that they throw away everything they've ever known and lay down their lives or else this relationship, possibly the first one they ever felt truly safe in, is nothing.