My girlfriend is getting into my nerves.

I have a Korean girlfriend whom I met in an international dating blog. I got problems with her in terms of being romantic. Don’t get me wrong; I love her. I like the way she is. I like it when she’s being sweet to me. It’s just that she’s too much. She is into couple shirts, couple rings, couple shoes and a lot more. I’m not into that. It’s fine with me though but not to the extent that we almost look stupid. I find it extremely childish. I hate it everytime she asks me to wear this and that. If I won’t do what she wants, she will stop talking to me the whole day. She’s getting into my nerves. Everytime I tell her about how I feel with those stuff, she will get mad. What should I do with her? Help!