You sound like you're married. Tomorrow, do me and yourself a favor by calling somebody else to have dinner with. Break away from her a bit and go meet another girl. Bring the new girl to meet the old girl and see what happens. Old girl may get jealous and then all of a sudden, you just became SO much more interesting. Or, she won't care and she'll find a new dinner buddy. That way you'll know where you stand with her
Not putting miles on your Ferrari is like not f*cking your girlfriend so she'll be more desirable to her next boyfriend.