If someone turned to you, someone you cared about and said that they felt the way you do, what would you advise them? Would you think that they should not love/like themselves based on lack of talent? Even supposing that is true, who is to say you won't discover some talent that you have in the future?
Acceptance is key. Accept that you're untalented, not especially likeable and all of the rest of it as that's what you really believe, but that you love yourself anyway. You need to take the pressure off yourself to be specific things and just accept yourself. One exercise I've encountered is to tell yourself 'I love you' in the mirror each day. It feels unnatural at first but with some practice it feels more convincing. Also, go out into the world and love other people. In my experience, at times in my life I've felt unloveable it's when there hasn't been much love in me for others either.