How do I know if I like someone?

Cos like I think I like someone but then I think about it more and start to think I just like the idea of having a bf/gf/partner 

Like I would think I have a crush on someone but then I’ll date them and the feelings of love and compassion never come around

I would love to cuddle and kiss someone and be called someone’s girlfriend but when I date someone I feel like I end up seeing them as more of a friend than anything else and then when we break up I get over them so easily, like I’ll be sad for a day or two but the feelings would fade and I’ll move on 

Is there something wrong with me?

Or am I just a shit person to date?