If I may make a suggestion V-Day is a perfect time to break up with her, if she see you are going out of your way to do cute stuff like go out to dinner or make her cupcakes and give it to her or even make her a nice card and put roses all over her car, she simply is seeing that you are weak and can easily be walked on. Now my guess is that you have a reasonably short leash, the honest to god best thing to do that day is look her dead in the eye while holding her finger tips and talking softly " Baby I just can't do this anymore I purely just want to fuck and whats not a better day than today and if you care for me you will understand" and your problem will be solved, lets think about the positives, shall we......?
1.
More money for JDM tight shit
2. No naggy/squealing and faking orgasms
3. A upbeat free spirted mood on life
4. Getting random BJ's from other girls and not feeling guilty.
I am glad I can help for any other relationship advice and/or tips feel free to drop me a PM. 