A comment I read somewhere said it best, for me:
Love - real love (not the kind of love that you're "in" - that's just an oxytocin high which fades after two years with anyone, be they sinner or saint) - is a choice. Without wishing to get too Jesus here, real love involves self-sacrifice. It's the desire to perform a selfless act. It's what we choose to give away. Hence why a mother might sacrifice herself for her child.
But sometimes that choice has to be weighed up against a cost. If all you get is pain - whether mental or physical - then at some point you're heart might think "what's the point?"
I’m in a similar boat. I love him but I feel I’m here for convenience. He pushes me away when I try to initiate physical affection unless he wants something.
Case in point!
If you care for someone deeply and you otherwise get along well and once upon a time you did spark, then love - real love - exists, or at least the potential for it does. Don't confuse not feeling being "in love" - those feelings wax and wane and if, like most couples out there who've got two young kids your stressed, lacking sleep and not seeing things pan out as the "Country Child" dream that you'd planned then sheer exhaustion will push things most definitely towards "wane". When we're depressed - and God knows dealing with two small kids can get depressing! - you can experience something called anhedonia: the inability to feel pleasure for things you always used to feel pleasure about, be it a hobby, music or, yes, your partner.
The truth is these things have a season. I've been there myself. But its also true you get what you give. And love is nothing if not reciprocal. If it's not, work on it and if that fails get out. But equally make sure you're not the one sitting there demanding the kind of giddy feelings that only the first two years of a relationship can bring whilst giving nothing in return.
If not having those giddy feelings is a deal breaker, if not having them brings you enough pain that you feel you cross that critical love/pain threshold then, sure, you have the right to choose to stop loving and look elsewhere. Just be aware you'll be back in the same place when that oxytocin wears off and you'll have to do the same thing again... and again... and again...