Reddit mentions of The Travellers

Of course she's insecure.

She's a young 20 year old woman who obviously likes you quite a lot but has no security over your intentions towards her.

You feeling the relationship is off, spending 3 years with her without actually marrying her will not make any woman feel secure in your emotions and intentions towards her. The fact that she asks you if you think the other girls are pretty shows that she doesn't actually know whether you think she's pretty enough or not. She also likely suffers from the same insecurity many women feel about their own appearance which is exacerbated when one feels like they are in some competition to gain the favor of a guy.

I have 3 pieces of advice for you:

1. Do not ever answer the question, "Do you think she's pretty?" You answer should always be, "I don't want to look at other women that way, it's a sin". End the discussion there.
   
   
2. Man up. Either marry the girl or leave her. Don't be wishy washy about your feelings. Had you been with her these 3 years in marriage, the security issues probably wouldn't be so big, and the longer you delay the decision in this off-again on-again way the bigger the insecurities will get.
   
   
3. If you decide to stay with her. Work on the insecurity issues and your own problems together. Don't just make it her problem. Buy a self help book or see a marriage counselor. Read through Islamic books that discuss what a good healthy marriage looks like, something like The Travellers. In essence, you should consider this a journey the two of you are going take together to improve yourselves and work on your weaknesses. No one is perfect, but you can work together to become better.