I agree with the above comment but what you haven't said is how long ago she came out of her former relationship and how long the two of you have been seeing each other. I think that does make a difference. It also could be she really likes being with you but is longing for some independent time as well with no strings to anyone. You are a part of this pair and you opinion and needs matter too. So, as the above poster said, you can let her know you want an official relationship (and that is fair for you to be honest) but she may not want that at this point and you risk losing what you have - but that might not be the end result it is just a risk - or you wait it out patiently a while longer (a couple of months) and see if you start seeing her more often, texting more frequently etc. and at that point bring the topic up again. There does come a time where if you want to be official and she is still putting you off you have to decide if it still worth waiting it out or if it is better to just move on. You'll know when that time is right because you'll be tired and frustrated and it won't feel so great when you see her. Hopefully, you two will work it out though. Good Luck!