Hard stuck on pre-Skeletron GetFixedBoi

hello fellow Terrarians! so, I’m getting pretty frustrated, because I’ve been trying to play through the GetFixedBoi seed because I’ve done pretty much everything else there is to do in the game, and I was progressing pretty steadily until I got to around the time I should be fighting Skeletron. I haven’t actually tried Skeletron that many times, but when I did fight him, he instantly curb-stomped me. I’ve tried Brain of Cthulhu and Eater of Worlds countless times, and I’ve gotten very close on both of them, but invariably they’ve decided to randomly despawn either right at the start of the fight, or right when I’m about to beat them. I’ve probably tried Eater of Worlds upwards of fifteen times, and it’s randomly despawned at least five. I genuinely don’t know what I can do to be any more optimized at this stage in the game. I’m alternating between Wizard and Ranger depending on the situation, and I’m using an Unreal Sandgun / Demon Scythe with full Shadow Armor / Jungle Armor and Imp Staff + Bewitching Table, and my accessories are Terraspark Boots, Sandstorm in a Bottle, Panic Necklace, Frog Gear, Magiluminescence, and Shield of Cthulhu (and sometimes Mana Flower). All of them are warding except for two, which are guarding. My mount is Chillet. I always use a major buff food item and chug at least two red potions + ironskin potion before every fight.

Nevertheless, every boss except EoW/BoC kills me pretty much instantly. Despite the fact that Queen Bee only has like 8k health, she kills me before I’m able to deal even 2k damage. The only bosses I’ve beaten are Eye of Cthulhu and Deerclops, and the latter only because it doesn’t despawn when you die. I’m getting pretty disheartened because I genuinely don’t know what else there is to do, and even if I do manage to kill Skeletron, I don’t think I’m going to gain access to much that’s going to make me that much stronger (Phoenix Blaster & Hellwing Bow will be nice, but not enough to make me the 5x stronger that I’d need to kill Wall of Flesh).

What else can I possibly do? I hate to just throw in the towel, but I’ve sunk 25 hours into this character already, and I’ve died 462 times and feel like I’m getting absolutely nowhere. Any advice would be greatly appreciated!