But solo of course he loves and cares about you - it's not surprising, you were his partner for a long time, there is a deep connection and you are being very forgiving to him.
But he is with someone else, who every day he chooses over you. Every day.
I know I came on this thread and mentioned my own parents before, this really is exactly like their situation. All my mums friends would say 'oh he seems to still really care about you, i bet he still loves you'. Because my dad , when with my mum , would love to sit there, with an arm around her shoulder, or having nice dinners...but then he left. Because he didn't want to be with her.
Your H probably doesn't want you to detach, this is a nice situation for him. But he left and is with someone else, how long will you allow yourself to hope he will come back?
At some point, you have to make a definitive move forward, or this energy vampire husband of yours will continue to have his cake, eat it and make trifle.