Think Milah was in a way overstating and in a way she wasn’t when she told Rumple that she never loved him.
Milah believed herself that she was in love with Rumple back before he went to the Ogre wars. She was not crazy about him going into that war. It didn’t seem to matter to her, that Rumple was called to be the son of a coward. Although possible at this point Rumple only thought people would judge him as that despite that they barely cared; think he was teased but it was not that much of an issue for others, he was more him struggling with the shadow of his father. Milah didn’t see any need that Rumple had to prove himself, but she supported him when he insisted to go to war. All she wanted was a good and safe family life. Impossible to tell by what we saw if she believed it was her one and only true love (if she at all believed in such a thing) or if she loved him as the best and nicest guy she could get in her village. She might have been not even able to tell by herself the difference at that time.
Being married to someone who struggled with being the son of a coward and sometimes might have been teased by people because of that, and being married to someone who irrefutable injured himself to avoid battle (no matter what more or less good reasons Rumple had for himself) is a huge difference of experience. While before it was more of a tease, a neighborly but not despiteful kind of joke, it now turned into a very real thing. Her husband was not the son of a coward anymore, he was a coward now himself. Pregnant and then with new born son Milah had to deal with despise and probably hate by other people because of that. Yup, her reaction was unexpected harsh when Rumple returned, but it spoke of frustration of the feeling that her, their dream of a good and safe family life seemed destroyed. Milah was without hope and without hope love has a hard time to survive, no matter how strong it was before. (after some musing by now understand better why she was reacting the way she reacted)
When Milah met Hook a few years later she experienced something that she never had experienced before, making her question herself, if she ever loved Rumple.
I find it interesting that the idea of one true love often seems to come with the assumption, that people know that this is their one true love, that what they feel at a given point in time for a particular person is the thing. How can anyone be so sure? I mean, is there something like some voice coming from the off announcing; that is your true love, dearie? It is possible that you truly believe to be in love with someone, but later you realize it was not that kind of love, it was not all true love, maybe not love at all (good for you if it never happened so far to you, but it happens).
Just read about a study about the impact of believe in “romantic destiny”, in that people are meant for each other or not, that there is something like a soul mate (in the sense of a person meant to be with you). Might surprise but the result of this study was, that people believing in the concept of one true soul are the ones giving up more likely on a partnership the moment difficulties arise. If anyone is interested, here a text about the study. Would have thought it’s the other way around, not? Or not. Problem is maybe more what we understand true love is then true love itself (if that makes sense to anyone)
Point is: with expectations high disappointment can be higher.
In short: Milah didn’t lie to Rumple, neither when she said to him she loved him nor later when told him she never loved him. It was just that she saw things very differently between these moments. She wasn’t superficial, not necessarily, she got a different view on life, on her life with Rumple.
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