I hate trainers, they are so boring. But if that's what it takes, you have to do it.
Besides the trainer, you can get lower gearing for your bike so you can make it up the climb home without killing yourself at the end of a long ride. I have a wicked climb to my house so I can sympathize. It took me years before I could do it regularly.
Another option is to bring the bike in your car and ride from work, or somewhere between home and work. That's assuming you have showers at work or join a gym nearby....