I wondered the same thing after the relationship with my survivor ended. At the time, he wasen't in therapy so he couldn't help me in finding closure for us. Like your husband, he would tell me he loved me but other times he'd tell me he felt he wasen't sure he ever loved anyone.
It was explained to me that sometimes a survivor will desire love and relationship so strongly that it is a physical ache, all the while he'll go to great lengths to push it away.
In my opinion (at least in my situation) I believe my survivor had feelings for me, that he felt for me what his perception/version of love was. But since his perceptions were twisted and damaged a long time ago, like Obi said...the relationship would have never grown or lasted. He hadn't the tools it required to maintain a "love" relationship.
I can look back now and imagine what it must have been like for him. Wanting what seems to come so easy for everyone around him, yet always waiting and knowing it would fail. It must have been emotionally exhausting for him....in his quiet time feeling he couldn't give me what I needed/wanted and eventually I would leave. And at other times since he didn't know what he really wanted or felt, how could he be happy with me or anyone?
"Escaping" sounds the same as running. My boyfriend and I would break up and then he'd come back and want to try again. He'd tell me, "I am so tired of running. I want to be with only you". So, yes maybe your husband found your marriage as an escape from his sadness and pain. Maybe he saw you as that, "safe" person who could save him. I think that's what my boyfriend was hoping. Even if he didn't consciosly realize it at the time. As the relationship went on he would tell me he "needed" me, more often than he told me he loved me.
His issues or the behaviors that result from them, has nothing to do with you... I know your head already knows that but in time your heart will feel it too. When that happens, you will have true peace and forgiveness for both yourself and him.