Hankster does bring up a good point...it sounds like something my ex would've done in a heartbeat. Mind you, my ex was a con artist to the nth degree...everything about her was a lie. I'm not saying that's what happened here, but I try to cover all the bases.
What really tips me off is when he says he's "not Jewish enough" to please you...ouch.

That's just spiteful, and I think aimed solely to make you feel bad so you'll reconsider. It *might* be, in a best case scenario, him simply responding while being hurt...if the breakup was quite so sudden, then I can understand that. Not the smartest thing to do on his part, as I would've advised he calm down before he respond, but not all of my advice is as easy done as said. But, back to my point, if he is being legitimate with you, then I feel like Webgoji's observation that he might resent his conversion to Judaism later is validated by his text response.
In some advice I could stand to take myself, being in roughly the same spot in life as you are, it is painfully easy to become in love with the idea of being in love. I found myself in that same spot about two years ago. Had a long distance relationship (mainly online) with a girl I fell absolutely head over heels for. This would be the one I mentioned in my opening paragraph...her betrayal was absolutely devastating, and I should've seen it coming all along, as the signs were blatantly obvious. I simply refused to see what was right in front of me because I didn't want to consider that this "first love" of mine was a lie. Again, not to suggest that happened here, but I relate it to you so that you can avoid the same.
lol At last getting to what you originally asked, I think telling your parents shouldn't be that hard of a thing.

Here, in this case, I think they may've objected to the age difference...my mother wasn't a fan of my ex and I's 5 year age difference, so assuming your parents are like mine for the sake of argument, 7 might be a little harder to sell. But otherwise, it's not that big of a deal.

You're right about it...they're going to be happy for you, and I don't think they're going to flip out or anything. For you, it's just the difficulty for expressing a personal emotion to your parents.

I have the same issue...the "I met a girl" talks with my mom are some of the most awkward conversations ever, and mom and I have very, very few awkward territories. I suppose it's a mixed blessing those talks come few and far between.
Sorry to ramble as I did, but I figured I'd address the issue broadly, and maybe help you later down the line.
Hugs, and I hope things work out for the best,
Harley