Stop questioning yourself.
I’m wondering if that is due to the relationship, or just my own mood and mind
Why does it matter? You feel the way you feel. Accept that.
There's no 'right' way to feel about him, or about the relationship, any more than there's a 'right' way to feel about any particular food or fashion. You wouldn't be trying to work out if your hatred of raspberries was a problem with raspberries or a problem with you; you just accept it, it's how is, and there's very little you can do about it. You wouldn't question your mood and mind if you didn't happen to enjoy the latest James Bond film; it's just how you are, it's a preference, and you'd accept that, even if a massive majority felt differently to you.
Your feelings are what they are. They're not under your control (otherwise people would be able to choose who to fall in love with, and the world would be a very different place) and all you can do is respect them. If you're getting enough enjoyment out of the relationship to stay, then stay. If you're posting on forums about it, you're questioning, and so it's probably not that fulfilling for you. So you could choose to do something else that would make you happier, instead.
But don't question yourself. Your feelings are your heart, and to query it is to disrespect it. Listen to it, and respond appropriately. Don't dismiss it.