I fully concur - i.e, I agree 'Ignore the ones who think you don't matter'. After all, there is not TIME in most people's HURRIED lives to take the moment to contemplate you or yr issues.
When I was younger (and in school), this chick called Ruth rose in popularity by pick, pick, picking on others. She'd be quite mean w/ her tactics; she'd point out things that she figured 'showed up' the person [as to their maturity].
It backfired on her within 1 year!