GAC Ruined by swgoh?

It sounds like your characters are poorly modded and you're lacking core game mechanic understanding (i.e. reading the kits of characters). GI will never beat Rey, regardless of relic levels. You're going up against people with smaller rosters because they perform as well, or better, than you. Skill and strategy actually matters, not just GP and relic levels. It's very possible for smaller accounts to punch up, especially when their opponents don't mod correctly or place teams on defense that are better offensively. Use swgoh.gg for GAC counters or to scout your opponents. What you're missing is game knowledge, not gear or relics.