I was afraid to be alone, I was afraid I couldn’t find anyone else and I was ignoring red flags, because you know…sex…
Another thing I would tell my younger self is that how much sex you have isn't a measure of how successful a relationship is. It's important to have a functional relationship outside of sex, especially if you want your romantic relationship to last a lifetime. There will be a point for all of us where physical health will preclude a normal sex life, so you best be comfortable with that before it happens.
What matters is they care for you, you care for them, and you both having matching values. Anything past that is just a bonus.