It’s an expensive solution (heck I can’t even afford it at the moment) but my solution for this was a personal trainer. If I have an appointment with a human being who’s expecting me and will be cross if I don’t show, I’m going to go. After I let the trainer go, I had a SO who would have raised an eyebrow had I quit lifting, so that kept me going until we broke up. In other words, if you can, enlist someone to whom you can be accountable.