well why not if it's consensual? the real problem is his parents how will they react? And she is wrong giving to much attention what other people think!
How can they even tell he's a highschooler when he's pretty tall. If the both of them dressed more fashionable instead of like mom and son people probably wouldn't notice them as much
I feel bad for this couple. Age insecurity is always gonna be a factor in this relationship especially when society has double standards about age gaps if the woman is older. On another note, he's not quite legal yet so some people might be concerned that she's a predator. I'd be concerned if a high schooler was dating a 40 year old man. They're a cute couple though so I hope they work out her age hangups. Another good option is to move to somewhere more rural so there will be less ppl to deal with.