I think that you need to decide to get over you last ex. You clearly have unresolved issues, and maybe you should work on these issues before you get involved in another relationship. You seem to be comparing your previous relationship to your current one, and that simply is not fair. Every person is different, and every relationship will be different. There will be good things and bad things all the time, but you cannot keep trying to replicate what you had with your ex.
Ask yourself if you still have hopes of getting back together with your ex. If yes, then why? Is it enough for you to try to get him back? Do you think you two can work through the problem? If no, then ask yourself why you are still keeping in touch with him, and whether this is really preventing you from pursuing a new relationship.
Otherwise, you are leading your current bf on. It doesn't seem fair to keep going out with him because you are afraid that things might not work out with your ex again. You are trying to keep the back door open becuase you are afraid of making a choice and living with that decision. Is that how you would want to be treated?
If you and your ex are both willing to work to overcome the problems that separated you to begin with, then I say go for it. However, if you are not willing to do so, I think you owe it to yourself and your current bf to make a big effort to end things completely with your ex and focus on your new bf, so that you can begin to have a truly happy relationship. You will need to stop comparing it to your past relationship, and focus on why you are now choosing to be with this new guy, what you like about him, and what kind of future you two have together.
In other words, I think you are staying with this current guy because you are afraid and unwilling to be alone. And yes, I think you are stringing this guy along.
Know that whatever these issues are, where he tried to improve then let it slip back, this will not change. The things you have asked for are not things he wants to do, that is why it goes "back to the same." If you stay with him, you cannot hope for improvement. Such a hope will only cause aggravation and reduce your affection.
"he knew something was wrong because I wasn't showing him affection. He said I needed to completely cut-off correspondence with my ex and show him more affection."
If your BF has asked you to show him more affection, and you do not desire to do so, then perhaps this is not the man for you.