Does anyone here use a cosleeper?

I’m getting desperate

During the night my son will sleep with me but as soon as I place him in his bassinet he cries

And if I lay him in his bassinet while he’s almost asleep he won’t go to sleep and he will cry

But the thing is, if I place him in his bassinet during the day he WILL sleep in it 🙃

I was REALLY against any type of cosleeping with my son in the beginning because a family member had passed away due to SIDS and my aunt had a situation while cosleeping (her daughter rolled between the crack of the bed and the wall-but she’s fine)

But with recent occurrences, I will be so tired in the night that I will fall asleep while nursing him no matter what I try to do to stay up

And I cant just let my son sleep in the bed as is because his dad is a super heavy sleeper and I do not feel comfortable letting our son sleep on the outside (or towards the edge of the bed).

So I’ve come to the conclusion that I do need to find a safer way to bedshare while I try to figure out how to “train” my son to sleep in his bassinet at night

And I’m curious what others use and what the safest options are