Rehearsal Dinner Etiquette

So we are having a smaller wedding, including FH and I, 69 people were invited, 37 who is family and 6 additional are wedding party and their partners (who aren’t family members). Because of the size of the wedding, I didn’t want to have a big rehearsal dinner because it would basically be the entire wedding. My fiancé, his parents and I were able to compromise so it’s just bridal party and their partners, our parents/siblings, and aunts/uncles. Than a small brunch the day after the wedding for just the bridal party and their partners.

So my question is, my cousin (in my bridal party), doesn’t have a significant other. I invited her to the wedding with a plus one and she’s flying in a guy friend from Louisiana to be her date (we live in NY). Luckily I’ve met him before so it’s not a total random at the wedding, but do I also now have to include him in all of the other events? Everyone else in the wedding party is married or in 5+ year relationships so I don’t want her to feel left out, but I also don’t know how I feel about including someone in a big life event that isn’t actually part of our life.

My aunt also has a boyfriend, whom I never met, and I don’t know if I’m supposed to invite him to the rehearsal either?

I don’t want to be a jerk, but also don’t want to feed every Tom, dick and Harry that happens to sleep in their bed that night.