OP, what you are doing here is make a 5yo (!) responsible for your mental wellbeing and for the hang-ups caused by your childhood. That is really terribly unfair.
First of all, it is your decision to equate being beautiful with being loved- this is not her fault and a terrible thing to teach her. She should not learn that beauty is necessary to be loved, or necessary for anybody's self-esteem.
Secondly, it is normal for a child that age to seem to prefer one parent: it doesn't necessarily mean they love them more. Often the parent who is spending less time with them and is consequently less interesting. Ds went through a stage (a little older than your dd, I think) when he wanted to see me as a terrible harpy and his dad as my downtrodden victim. Dh and I told him off when he strayed into rudeness but otherwise just laughed it off. It took a few years and then it passed.
Dd had terrible tantrums where she would bite and kick me (rarely her dad)- again being calm and not taking it to heart was the thing that seemed to work. Both children now grown up, on excellent terms with them, both seem to have a good deal of respect for me and have no doubt at all that they are loved.
Your job, as the parent, is
a) to teach your dd to be tactful- which is not done by asking if she thinks you are beautiful: that is precisely the kind of thing she should not be encouraged to comment on.
b) to show her that your love is so strong and so unconditional and so confident that it doesn't matter what she feels: you have enough love and strength for the two of you.
c) to show her that though words can be upsetting she does not, at 5, have the power to make a serious difference to the adults around her. She can't break you: you have the power. If she can't feel that you have that power and know how to use it, the world becomes a terribly scary place for a small child.
Appropriate responses to
"Go away I don't want to see your face"- "Now don't be rude/silly, dd; I'm not going anywhere"
"Daddy is beautiful, not you" (not that this should ever have arisen)- "I'm glad you think daddy is beautiful, I do too, but you mustn't be rude about me".
Briskly, cheerily, practise in front of the mirror.
Never ask if she loves you, never ask if she thinks you are beautiful. She will rightly sense that you are expecting her to make you happy and that is more than she can cope with.