Why are you not valid and worthy? Have you ever set a dog on fire for shits and giggles? Have you ever molested a child? Violated a person's sexual consent? Sold any one into sex slavery? Robbed an elderly person of their valuables and hit them in the face with a crowbar? Murdered someone and dissolved their body in Lye? Shot up a school? Bullied someone and laughed at their distress and made a pattern of doing so for years?
If the answer to all those things is no, trust me when I say you are more valid and worthy in this world than many are.
There is no shame in seeking out validation if you are not getting any, where it matters to you. That does not make you pathetic, no more than a person dying in a desert of thirst is pathetic for asking for water. It is only a problem if you define all of yourself on the basis of how others view you. If you succumb to that you lose yourself.
My own personal validation comes from being good to my loved ones, and trying to share with them positive experiences and getting plenty back from them that proves they value my presence. My former work used to be quite validating as well. I also try and validate myself by acknowledging what I have achieved in areas I was actively trying in. Even an incremental step is worth valuing, especially when starting something can be harder than finishing it.. Sometimes it is also worth reflecting on if you upset a person by saying no. how that may actually be a good thing. It means you have boundaries and will defend them even if it robs you of validation from some people. You can't please them all and nor should you try to, unless you want to be a doormat to everyone and not live out your own wants.