First thing, don't make a scene. Don't try and catch her. Because however you do it, it will only leave you looking like a jerk, or very needy, or worse - both. And if you pull off looking uninterested about it then you're right back to play games with her. It might peak some curiosity on her part, it might work, but most likely it won't and you won't be able to maintain it over time. She probably knows you too well. She is not doing anything wrong. Technically she does not need to tell you if she is dating. Her discomfort about broaching the subject with you is very understandable. It doesn't necessarily reak of lies, but compounded with other behaviors it could be a warning sign.
The situation sounds very unfortunate and I feel your pain. By not communicating you alienated each other emotionally, and the physical aspects didn't help. A lot of people don't desire physical intimacy when emotional intimacy is lacking, especially when SSRI's and depression and other factors (like your doormat status) complicate things. It was a large misunderstanding and yes it might be salvageable, but this is not the way. As several people have stated, myself included, being the doting boyfriend to the extent you were is not only unhealthy it is begging for disrespect. If you have any chance with this girl, it is not by setting yourself up to be walked on more.
Red Mercury said:
EDIT - Also, is there not a bit of irony that the way in which I first reacted, in terms of moving out and initially cutting contact, is the way that I should be acting now?
And no, your first reaction is not how you should be acting now. Your first reaction was wrong. You should have clarified things with her, communicated before jumping to conclusions and saying or doing something you didn't mean or want. You went from acting like you didn't care if she cheated, which sends a bad message ('walk on me' and/or 'you don't mean much to me') to making it worse by casting her aside.
What you need to do now, and I can't guarantee it would work but it would salvage yourself - which is more important at this time, is express an interest. You'll always regret it if you don't. Communicate it however you feel is best. A long, proof read again and again letter perhaps explaining the misunderstanding, your feelings towards her then and now, your realization you've been too soft in the past, your determination to fix this in the future (starting NOW), your understanding that yes it seems to be for the best if the two of you live apart for now, but that you want to work on things with her, gradually if you must (though I'm sure you'd enjoy something faster). If you don't want her to date others then state it. And no I'm not talking about that pathetic 'I want her to be happy' crap. Do you really want her to date? If the answer is no, then say it! And let her know in a *non threatening* way that you will be moving on. If she comes around before it's too late great, if not, then while you'll be heartbroken you won't let it stop you.
It is not her place to tell you that she doesn't think you're ready to date again. It seems awfully hypocritical of her considering, and almost like she wants to keep you in line for the future. Play the field now, keep the fun for herself, while you wait and suffer thinking she's doing what you are. No. Absolutely not. I am a sucker for true love, and such a glutton I myself would remain single simply because I wouldn't want to date, there would be no drive. However, I wouldn't hold myself back if there was any interest in anyone, because she's clearly not.
Red Mercury said:
Besides, I don't think I could ask her to be exsclusive with me, when its obvious its not something she wants.
Yes you can. Have more respect for yourself than this. If you date her while she is dating around you're just screwing yourself over. You won't win her back, you won't be getting what you want, you'll just lose more self respect, she'll lose respect for you, and you'll just be closer to the damage she does to your heart. If you put down your limits, consider what makes YOU happy you can gain respect for yourself, show her (and tell her if you like) that you value yourself and your feelings for her too much to let them be cheapened like this - you might stand a chance of winning her back. You might not, but you can at least walk away knowing you have your self respect, and you have developed a back bone and hopefully developed some skills and restraint that will pay off in the future.
1. She comes running back.
2. She dates a bit and eventually works her way back to you.
3. She becomes involved with someone else and never comes back.
All of those are better than being the second fiddle as another relationship develops right before your eyes. Emotional torture, don't do it!