If you’re autistic, there’s a good chance that autistic masking is the root cause here. If you have social anxiety especially, your mask will kick in automatically (subconsciously) and come off as fake to most people, and they will not like you for it. A quick test for this is, are you good at making a good first impression or short time of friendship and then it kinda falls off with time? If yes, masking is likely in play. I highly recommend the book Unmasking Autism even if you’re not autistic. It applies to others as well and it is excellent.
The short term (maybe long term…?) solution is to make autistic friends. They’ll understand “the weird” and it should be much simpler. Try searching around your local area for autism or neurodivergent clubs and see how you feel around other similarly-minded people.