Well lets look at the scene:
It's very carefully done - look at the choice of artistic viewpoint: every shot in the scene emphasises the size and strength imbalance between the small, terminally ill Jane, and the tall and powerful figure of the immortal Thor. The "camera" looks down on Jane's frail form in shots that centre on Jane, emphasising her vulnerability, whilst shots centring on Thor look up to his face from a lower perspective, emphasising his physical domination and aloof stance. The visual of the power-dynamic between the two is really well done, beautifully thought out, and totally unambiguous as to what it is trying to convey.
The dialogue naturally is in the same vein as the pictures, with Jane baring her feelings, her fears and her insecurities, in heart-breaking fashion; Thor, on the other hand, is shown to be petty and mean-spirited, and is, unlike the reader, totally unmoved by Jane's plight. Not only does he ascribe petty motivations to her acts, but he also throws in the fact that he cheated on her back in the Lee/Kirby years. Now I'm sure most of us, mainly when we were young, have been in an argument with someone (usually a parent) where we were feeling petty and self-pitying, and accused the other party of doing things out of petty reasons, flipping motivations around in order to keep the high ground - this is immature, but basic human nature; what you NEVER do in those situations is make up a lie that puts yourself in the wrong, because that actively goes against the whole point of suggesting it is the other person who is being petty whilst you have the high ground. It just doesn't happen.
You are literally the only person I have seen who has said that Thor was lying about cheating on Jane. Last time I asked for a show of hands, I think all but you thought the writer intended the reader to feel Thor was being honest. It's a retcon, and one that makes little sense other than to further remove sympathy for Odinson from the reader. One of the basic themes that has come out of this run is juxtaposing how Jane deals with setbacks with how Odinson deals with setbacks, with Jane generally shown to be positive, brave and classy, whilst Odinson has been shown to be petty, self-pitying, and entitled. In Aaron's writing Thor is not the noble and admirable hero of Lee/Kirby, but someone clearly shown to be lacking in the qualities that made Jane popular, qualities that Thor used to have. Aaron's Thor is a poster boy for toxic masculinity. And this is not Aaron suggesting that this is just Thor going through a rough patch, we can see from the flashbacks to Thor's younger days, and the aforementioned cheating confession, that Aaron is telling us that Thor has always been like this at his core. This isn't just me reading what I want to see in the writing, because God knows this is not what I want to see in a Thor comic, but it is what is down on the page. You spin more than an industrial drill-bit in order to cast Aaron's writing of Thor Odinson in a positive light and try to make it the reader's fault he/she isn't happy with the characterisation, but it isn't going to happen.
Jane's Thor is popular because she is easy to empathise with, heroic, admirable, smart, and powerful; in short the reader is put in her shoes and feels empowered. that has always been the trick to making super-heroes popular. Aaron has deliberately moved away from those qualities in Thor Odinson, the qualities that made him popular, going so far as to pretend he was never like that in the first place. Why would he do that? How does making Odinson so much less than he was, so much less relatable, so much less empowering, help him and his popularity as a hero? I don't think it does. You can get very positive things out of temporarily removing a hero's advantages in a story - Thor:Ragnarok used the loss of Thor's hammer to make him a sympathetic underdog, help him grow as a hero, showing that he could be greater than ever without his trademark hammer, and that worked great; similar things have been done in comics with Captain America losing his heroic identity and shield, even losing his super-soldier powers, all to showcase that those things are not what makes the character a hero, but the way they rise above their problems and deal with the setbacks life throws at them. Aaron has deliberately avoided doing these things with Thor Odinson. We could have had Odinson exercising his storm powers without the hammer - it would have been logical to do so - but no. We could have had Thor showcase his thousands of years worth of fighting experience, of strategy, of adaptability. Nope. I don't think Aaron is comfortable writing Thor as the kind of hero I want to see, the kind of hero he used to be, and that's why I want him off the book and away from Thor as a character.
His Odin sucks too.