2 month old seperation anxiety from me

My 2.5 month old son seems to have major separation anxiety from me and is extremely high needs. He cannot sleep on his own without being held, has to be rocked to sleep, and now throws horrible screaming tantrums and episodes if he’s being held by my husband at night and it’s bedtime. We want to sleep train him to sleep alone but I’m already feeling so defeated. He can be set down for a little bit during the day but he gets upset pretty quickly and definitely won’t fall asleep. I can’t even take him on a walk without a meltdown. It’s been very isolating and depressing. I feel very alone….hoping to connect with some other moms who are experiencing the same.