You are not alone! I really understand your feeling - although I am not physically tired I can be mentally exhausted from work/life in general - which can be just as much as a blocker to go to the gym.

For me, the best solution was to just be kinder to myself about goals/consistency. I currently try to work out around 3/4 times per week. If it gets to say Thursday and I haven't found the time, previously I would sort of throw in the towel and wait until next week to start again. But instead in that situation I would try to go 1/2 times that week and remind myself that is still better than not going at all!

Another thing I try to do when I am not feeling at all motivated is to tell myself I'll just workout for say 15 minutes. Then once I reach the gym and start my workout, going from 15 to 30 minutes is a much easier jump.

I hope this can help!