There are a few reason why this could be happening.
It sounds like when you are in a relationship with a good woman it does not spark your interest because I feel when it comes to being attracted to someone they need to attract your attention.
People have certain qualities that they find interest them when it comes to relationships, not everyone has the same ideas when it comes to attraction.
You seem to need a mixture of both personalities, you need a girl that sparks your interest that you can be in a relationship with long term.
Right now you have not found that one person that fulfills all your needs.
Basically you have not found the one, just yet.
You can try focusing on a girl in a relationship, making her feel loved, but that is not what you need. A relationship is 50/50. You can not just go through the emotions and expect to feel something.
You need to begin relationships with understanding each others wants and needs.
If we just look at you intimate desires, they are different from what you feel a relationship is, but
you can have both. You can have that club girl that sparks your interest and be in a relationship with her.
You seem to be attracted you feel to the wrong girl, but maybe it is not so wrong. This is what your desires are, but it also sounds like you want to be in a relationship as well.
When your in a relationship you could be feeling pressure to be the perfect boyfriend.
It is easy to not have that emotional attachment because you don't have to worry about anything. When you fall in love the emotions that are involved are intense.
They are often overwhelming and some people would rather walk away then feel these intense emotions or get hurt.
You will know when you find the right one because you will want to spend the rest of your life with the person and you will also be very passionate and attracted to the one you fall in love with.
You also might not be ready just yet to be in that fully committed relationship. Take your time and find the one that best suits you. You want to be in a relationship not where you are catering to someone wants and needs.
You want to be in a relationship where she thinks about you and what you need. It works both ways in a relationship it can not be one sided.
It is important in a relationship to have communication and also to have that physical attraction that keeps that spark alive.