No, you're not the only one. I think at least part of the Terry-hate stems from the fact that most fans would rather see Donna paired with another superhero (of either gender) than a 'normal' guy. I remember the only objection I had reading this all when it came out was the age difference--not to the point where I saw it as 'creepy', though. I just thought it was silly for her to fall for someone older when with her Amazon powers she'd probably seriously outlive even someone her own age.
At thie time I thought it was kind of cool for a superhero to have a significant other from outside the business who knew about their secret identity. I didn't personally find Terry attractive, but I was fourteen. If Donna liked him, that was her business.