Have you looked into co-dependency? It seems to be a real factor for many of us whose significant others are addicts. You end up stuck in a cycle with them and they are almost addictive to us… It’s taken me a long time to mentally start to break free of it.
The part you said about you loving him and him not loving you – the way I see it is they love the drugs/drink/addiction and in that sense they are incapable of loving us. They need to be able to love themselves enough to stop the addiction first before they can love anyone else.
It’s just a completely toxic situation to try to be having a relationship in, in my honest opinion. This toxicity is never going to make you feel good, fulfilled, happy, stable etc.
It’s really good if you can focus on your girls and yourself and turn your mind to anything other than him. Don’t let him stop you from you living your life… don’t him drag you down with the sinking ship. Cos that’s how I feel… I refuse to be dragged down anymore and I choose to swim.