I still can't dump a dumbbell if I fail without risk of injury, even if I'm to aggressive getting onto the bench you can easily injure your shoulder with 40kg+.
I think Candito has a video about how to bench without a spotter, basically just says leave the collars off, and if need be you can just tilt the bar and the weights slide off. You can always just roll it, be mindful with your reps, or bench with safety bars of some form.
Last resort you could just get some friends, and hence a gym buddy.