Hi, Izraehl, welcome to PsychCentral (PC). I have a sense of humor like/enjoy your girlfriend's too. It sounds like she thinks a lot of her own quirky thoughts and you haven't gotten use to how she thinks. Does she say "random" things to you sometimes?

I would collect the things that the two of you laugh at together, and bring them up in other situations, after you all have already laughed at them. I think you will feel better if you can have private things to refer to, that you both enjoy and can re-enjoy in other situations. Or, note what she laughs at herself and bring it up again, with you as the actor or modify it but only enough so she still "gets" what you are referring to. If she surprises you in the next couple days or really looks good, look at her like the guy looked at the line (but with more of a leer if she's looking really good :-) and say something like "This IS happenin!" and slowly walk toward her, appreciatively, ask if you can get in her line