Let's talk for a bit about the blame game.
In these situations, I don't think it's fair to put blame on anybody. Nobody did anything wrong. You've got nothing you blame yourself for, and neither does she. We like to put guilt on ourselves for a number of reasons. If you can bypass that, you're going to feel a lot better for it.
If you really feel guilty, than you need to find an appropriate way to apologise so that you will let go of the guilt. That said, I don't you're in the wrong from what I've heard, so I presume at this point the person you need to apologise to is yourself. How you accomplish that is beyond me, since it's different for every person. The important thing you're trying to achieve is self-respect. That's an important tool to have in fighting this battle.
Being at work right now can't be easy on you. Be proud of yourself for committing and not locking yourself away like I did. The fact you're trying to is incredible. The heart isn't an easy monster to fight, but with time (unfortunately), it will submit. Just keep holding on.
Sometimes, it might help to remember the good moments you had with her. The key is to do your best to avoid the feeling of loneliness after you get that boost of happiness. Again, being able to write down things might help; if you write down what the best things about those moments were, you might come to find it wasn't specific her that made you feel that way, but things she did and other things that occurred.
Since I'm not a professional, I can't really give 100% perfect advice for this situation. If you're really suffering after a few more days, you might want to consider a therapist or psychologist. Mental Health issues are very serious, and if you are undergoing severe depression, it's best to let an actually trained individual give you the support you need. For now though, just focus on the positives if possible; you have a job, you have some awesome friends, and I'm sure there's a lot more going on in your life which I could only dream of.
Dreams speak a lot about what we want. I'm not a pro at dream brown townysis, but I'm sure we can all guess that the dream was talking about you two coming to peace. I don't necessarily believe that means love, so I think your subconscious is probably also ready to move on. Again, not a pro, but that's how I'd take that. Keep logging your dreams, since they may have important clues on how you feel and how to make you feel better.
Think carefully about what it is that actually has changed between you two. I found that made things a bit better, since I realised that there's not a lot in a partnership that you can't get in a close friendship. Hopefully, you'll be able to see that this may even end up bring you closer together.
