Honestly, yes, I would anticipate that any romance written by someone who has never had one will inevitably feel inauthentic. (Also, a lot of romance novels feel inauthentic in general.) That is not to say don't write it, as practice will make it better, but it will likely take you more effort to get those parts right.

Your homework is to date people. That will improve your writing. If you have trouble getting dates, just lower your standards.

Also, even if you have a weakness, it does not mean you will not be successful. I read a lot of sci-fi, and it was a male dominated field for a long time. A lot of the writers write just terribly inauthentic female characters, but I can still enjoy the novels.