You are not over your ex, and you need to let this new guy go. Bringing someone else into your life when you haven't healed from a past relationship isn't fair to you or them. You appreciate the feeling of being with someone and I'd say part of you is scared to be alone but you're feelings for this guy don't really run that deep, you're using him to fill a gap that can't be filled by another person. It comes from you. Every person needs time to be alone after a break-up, to heal, to move on, to learn and grow from their past. Only then will you be ready to find someone new, and this could take time. But being with someone else when you haven't is a bad idea, because you spend all your time with them wanting something you can't have and you give them false hope. Let yourself be alone, do things that doesn't have you thinking about your ex 24/7. Go to the gym, start a new hobby or activity, do things you enjoy. The more time you give yourself to just enjoy living independently for a while, the less you will start to think about your ex, and the more ready you will feel moving forward.