I feel like my nipples are too big

Get into a lactation consultant and yes, keep attempting to latch but don’t force it multiple times a day if it causes baby stress.

Lots of skin to skin, keep offering but low stress situations

Agree. Basically set yourself up on the sofa/bed with lots of comfy cushions and all your snacks/drinks/entertainment and just have baby on your chest skin to skin and every time baby stirs offer the boob in a laid back position. Have you tried the hamburger hold? It can make the boob more manageable for baby. Make sure baby is nose to nipple and is tummy to mummy and has room to tilt his head back to open his mouth wide enough. Have some expressed milk on hand to offer you could use a syringe if you don't want to use the bottle. Can you see an ibclc?

I had to bottle feed for a few weeks (after BFing the first 2 days) and getting him back on my boob wasn’t easy but a lactation specialist made a massive difference! With her help we ended up exclusively breastfeeding for a year, it’s definitely possible to get him back on boob

I would see a lactation consultant. They can help with the latch and different positions!

Are you pacefeeding when you bottle feed? Babies tend to prefer how easy it is to drink from a bottle and get frustrated at the breast because the pace is slower.

Supplementing can also negatively affect your supply if you're not removing milk when you give formula. That can be adding to it. Can you see an IBCLC? They have more education and training than a LC, so safer to get the best advice from them.

The advice on skin to skin and removing stress is also helpful.