You probably could guess that I am a BIG supporter of PFLAG.
You do NOT owe any group anything! Do not let ANYONE pressure you to come out when you are not ready. I believe that coming out is a highly personal issue and only YOU can know if you are ready -and want - to do it. A good representative of PFLAG helps people find support when needed. That’s it, not to be out. Maybe they see something you’re missing but, from what you say here, I’m disappointed that a group, especially PFLAG, would put pressure on you.
Do you live with your parents? I would be very cautious around abusive people. That makes me uneasy. You don’t have to come out to your parents while you are in “reaching distance” of their abuse. If they are emotionally abusive, you may need to get counseling before you’re strong enough to deal with that. (trust me, I’m still working on that and I’m WAY grown up).
Perhaps you could tell them right out that you are uncomfortable about feeling pressured and you will come out to your parents, or not, in your own time…but you appreciate their concern for you. It does sound like they may feel close enough to you that they feel they could give you such advice. With abusive parents, it must be nice to have a PFLAG family. Though- if you come from an abusive home, you may be conditioned to obey adults, in which case, you feel you need to listen to these people. That makes sense- I hope you will seek counseling to work out the crappy parts of your life sooner - rather than later.