1. The -in' suffix is not standard English.
2. Otherwise, the grammar is correct.
3. What is the person doing? Loving. "I am loving it" has the subject, I, the verb, am loving, and the object, it.
4. All verbs have an -ing form. No exceptions! Love and hate are verbs (I love you! I hate you!), so they have -ing forms.
5. I've never heard this slogan.
[I edit copy have tutored college writing.]
Student or Learner