The feeling of wanting to be loved yet also not feeling love

Hi, I know this is gonna sound cringe (I get that) but sometimes when I'm in a relationship I don't really feel love.

Like I honestly don't express emotions like being happy, falling in love or even just positive emotions. I was wondering if anyone has ever felt the same way. 

In my past relationship I've been told to be more romantic yet I don't understand romance. It feels like there's a hole that needs to be filled 24/7 then replaced. Like I'm feasting of off something I can't taste. Like I'm listening to someone when I can't hear. Like I'm feeling for something but it's not near. Yes I know I rhymed there a bit but it's true, the only emotions I usually feel are quite blue.

I don't express love how it "should be expressed" my love is very complicated and very hard to get off my chest.

I've been treated with love in various ways and all in those ways felt not real. I mean yeah I do want a relationship but it's so hard falling in love and someone being in love with me. 

I don't know if the way I've been treated in the past has something to deal with this. But if so let me know so I won't feel like I'm the only one 

I've also been told to smile at times when I don't feel like smiling ( plus I usually don't smile unless I feel like it tho even when I do it feels fake)

Like genuinely it feels fake when I laugh or even smile like I can't feel or get any emotions from it which makes me think something's wrong with me.

And no this isn't a vent but more like a relatable thing that some people could relate to. I wouldn't mind seeing what other have to say about this or about what they relate to in this random rant. But yeah feel free to tell me I might be going through or what y'all might even relate to.