Suffocation Death when entering Nether Portal from either side

Reporting to bring attention to this bug again. I have now died from suffocation 5 times when using a nether portal. Either side has blocks of clearance. To another character, I appear to be standing in the nether portal as normal. When suffocated, all items disappear.

Once, as soon as i started taking damage, I closed the game, and upon restart found myself alive in the overworld, but standing at the coordinates i was previously at in the nether. When i tried this the next time, I suffocated before the game closed for some reason.

This is a major issue, and needs to be taken care of as soon as possible. I will continue to report it when it happens until it is fixed, as every time this occurs it destroys a half hour to an hour worth of work. If it can not be fixed in a reasonable time span, then i will need my subscription fee refunded for my realm.