Sadly, this is often true.
There’s something called, "crab mentality," based on the phenomenon that when you have a bunch of crabs in a bucket, if one tries to escape, the others will pull it back down keeping it in the bucket.
It’s not just “animal nature,” it’s human nature, too.
It’s scary for others to think that you’ll succeed.
In your success, they (subconsciously) feel they're defined as failures. And they don’t want to be faced with that.
You’ll only recognize this when you start on a journey towards a new goal or begin making serious improvements in yourself and your life. Suddenly, the people who love you, start criticizing you.
Questioning you. Doubting you. And scaring you with warnings, “be careful because what if…”
It’s rooted in fear, jealousy, insecurity, and more. Their reasons vary.
Your sibling wants you to fail so you don’t look “better” to your parents.
Your best friend doesn’t want you to succeed and leave them behind and alone.
Your co-worker doesn’t want you to shine in front of the boss because maybe they’ll get cast aside or let go.
This doesn't make them bad people, just scared. Big difference.
But you have to decide whatever their reasons, you won’t stop pursuing your goals and dreams. You might need to rely far less on the support from those who'd rather have you fail than succeed.
As writer E.M. Forster said, "We must be willing to let go of the life we have planned, so as to have the life that is waiting for us."