How do I know when to leave my husband? Life with him looks perfect but I feel empty.?

We've been together since high school, and our life together looks perfect to the outside world. Beautiful big new house, dogs, great jobs, etc. Last year I almost left and ended up starting having an affair. He didn't want to lose me and committed to becoming more attentive, respectful and everything I need. He provides everything for me, but I feel he still lacks respect. I have a good career and could afford to be on my own, but terrified to take the leap. In every other way he treats me well, but I just don't have love for him anymore. I crave touch, but not necessarily from him. I don't enjoy making love, and lately I've started hoping that he comes down with a fatal illness so I don't have to make a decision. I'm still seeing my boyfriend from last year. He makes me feel great, but he's also married and not likely to leave. My life looks perfect, but feels so wrong. I just want to be happy. I'd like to hear from people who have gone through something similar, and your decisions.