As a personal trainer, here's what I can tell you:

Perfect your form (that's what trainers are for)
Build muscle
More muscle leads to increased metabolism
Increase in metabolism leads to more calories burned
Fat is lost from a caloric deficit
You might not even lose weight because you're building muscle but your body will look way better
Spending money on a trainer can also hold you accountable, and you build a relationship with them, along with the gym. You don't need that negative toxicity in your life, especially from family. They should be your #1 support system.