Your making a huge error. You can't proceed from "I really like you" to "I really, really, really like you" to "I love you" just like that. You need more base. I'd recommend these workouts during the base phase:
4 x small present with 1 week rest
3 x sudden longing stare deep into her eyes followed by "just looking"
2 x nice dinner dates with 3 days rest in between
1 x not trying to hook up with her all night (builds post-nuptial shutoff tolerance)
When you're ready to peak try these:
1 x all out hand holding with your girlfriend in front of your guy friends
1 x snuggle up in pajamas and watch movies night (instead of getting roaring drunk with your friends)
4 x trimming nose hair
You should aim at 8-12 weeks of base, 4 weeks of steady workouts, followed by 2-3 weeks of a downward taper to "I love you".