Cool... I'm not going to quantify "love", but in those early issues, especially ASM #11 & 12, you can clearly see Peter being head over heels about Betty... So to me, Betty was his first "love", and I get that it paled in comparison to what followed with Gwen and then MJ.
Yeah. It's funny though how throughout the years, they've raised MJ's status as the one with retcons/reveals about the past, etc... though I get why the writers/editors would do that because at some point, Gwen became more "meaningless" (for lack of a better word" to the readers except the old troops.
I know she gets referenced in flashbacks, and alternate Gwens have appeared, and Peter gets "weird", which must even be more "weird' to newer readers.
In any event, I hear ya about Gwen being the first "true" love.
Though in my opinion, Stan wrote her into a corner with her father's death, because in those issues afterwards, she was just all two-dimensional "I hate Spider-Man for my father's death" ad nauseum, gone to London, cool trip to the Savage Land, and then BAM! Gerry Conway does the unthinkable probably more because he didn't know what to do with her (I keep hearing Romita Sr was pushing hard for that story too, who knows)
Cheers.