Jiakhan said what I was going to say- I have been a person like that since I can remember.
For me at least, it is not so much of me wanting to hear that I am pretty and so on- no, cuz even that with me will think others are just saying that and the truth is something else of what I create in my head.. I have issues with taking compliments as well from Real Life People that say I look nice-- I think what the hell do you want or what do I look like **** the rest of the time??

Low Self Esteem and so on for me- trust issues, and probably a bit other things that I have not yet to get over from my past... Plus just my self image some days.. If I feel, really bad or feel like a failure this bad self talk and no one loves me for real can get worse. For me it comes and goes as my cycles or when things are going on in different lights.... My brother in my family circle, is one that gets angry with this stuff cuz I think he relates to it in a way but then knows in some cases why I think I am crap or ugly or so on, like it reminds him where it stems from I think.. Well I think that cuz He has brought up- if so and so did not do this, you would not be this way....
My boyfriend really does not like it either, obviously cuz he cares..
I try best to keep myself to limited people with these feelings, people that I trust more, due to it is exposure....
Each person is different, your Family Member could be like me, or your family member similar , or just complete different.
Low Self Esteem though can do a lot of damage as I am sure you know... If it is extreme perhaps therapy, or I am sure there are a lot of websites that could help with self esteem improvements.
In the end it is the person that has to accept themselves for them..
I remember when I was about 19 I actually looked in the mirror and called myself "OK" as in I don't look so bad, I am not a true hideous monster.. I still do it from time to time, to remind my self, I am not as ugly as I have thought or think at times.