How much time should I give him?

I left my husband a year ago because I was unhappy and angry in our marriage. I never felt like a priority and he was always so indecisive about everything. I moved in with my new boyfriend about 3 months after I left my husband. I knew from the moment I uttered the words that I wanted a divorce, I was making a mistake. However, my anger and frustration got the best of me and I started seeing this new guy who was actually a friend of mine for many years. My husband moved on as well, only he ended up having his girlfriend move here from another state and now she is living in what was once our home. I have since broken things off with my boyfriend and moved out. I decided that after a year of not seeing or speaking to my husband, that I wanted to work things out. He said he still loves me, is still in love with me and misses me terribly. He said he made a mistake having his girlfriend move in so quickly, but that he doesn't know what he wants to do. I am sure that it is difficult for him to tell his new girlfriend this news. I have not given my husband an ultimatum or a time frame, but I don't know how much time I should give him before I tell him that I'm moving on. I don't want to wait for ever and I feel that if he isn't willing to be upfront with his girlfriend and tell her to leave so that he and I can try and work on our marriage, that he truly doesn't want to be with me. We've been spending a lot of time e-mailing/texting and going to lunch together. I miss him a lot, but I don't want to fall back into the old pattern of me having to fight to make every decision for us and feeling like less than a priority. Does anyone have any advice on how much time I should give him to make up his mind?