Since you two are girls, you can get a dildo. If you don't know what a dildo is, then look it up. But here's a faster definition: A dildo is a fake penis used for personal pleasure when the girl does not have the pleasure of having a man around. A dildo can look, and feel like a real penis and can be used for masturbating or sex with the same sex.
Buy a dildo and take turns using it. First, you use it on her, then she uses it on you. But this is only if you two want this and if you guys have gotten this far in your relationship.
If sex isn't the way your going towards then here's this. Go out together to a nice restaurant to eat. Spend some time together. Take a stroll down the park or watch a movie together. Do something together that the both of you would like. If it's music you two like then go to a concert. Or if you both have the same hobbie then do that too. Good luck.