Absolutely not! my girlfriend has freckles all over her face. They're light but they're there. What do I think about them? They're cute! Adorable in fact, and she's still easily the most beautiful woman I know. This is fact. She's awesome. I love her freckles and I think you should try to get over it. Why? I think yours are probably awesome too. So don't worry.
I can also tell you that your problem could me much worse. Assuming we can even call this a problem at all. Once I met a friend of my GF's at a comedy show. Her friend is this girl in improv who has freckles like all over her body. These big spots kinda like birth marks all over her body. They're the color of a paper bag basically. How do I know they're all over her body? Well admittedly I'm just assuming, but I'm making this based on how she was wearing a tant top or camisole or something, and I could see it all over her neck, shoulders, back, and arms.
Point is, the freckles thing could be much more extreme, and even in the case of that one girl, I still thought she was quite attractive. Did I think the freckles were too much. Nah. If anything I think it made her much more interesting, and who knows, It's probably part of where she got her sense of humour. She still looked good. Would freckles make a girl less attractive? I don't think so. would a guy write a girl off because of it? Well I wouldn't. I think that's really much more of a chick move than anything else.
What you need to do, is start embracing it. I bet you're just low in self esteem. You're probably quite attractive already, you just have trouble getting past what you think are flaws. It's just something you need to learn to live with. Cheer up. It's not as bad as you think. It hardly ever is.