If you were going to have things turn around for you within a year for the better, tell me, what would you have to do differently?
By that, I don't mean how would he have to change his behavior for you to feel better. You don't have control over that, right? That would make the outcome hang on what somebody else would do, and that means it's out of your hands. I bet you feel like you need more control, not less, right about now.
I mean what would you have to do that was a change in your behavior that would improve the situation purely from where you are; from your position in the relationship today?
Get another computer, and open your own e-mail account with no link at all with his? No?
How about making a point of telling him something you love about him every day, something real and, if possible, new? And real. I said that before, but it's worth saying again.
Start a short conversation with him once or twice a week about a subject of mutual interest? Maybe not stamp collecting or Giant Trucks, but if there isn't something now, this might be a good chance to find something new. That could be fun in itself. A short conversation, so that it stays fun. If the conversation stays fun and wants to get longer, it'll let you know.
None of these are back-breakers, all of them are small, and none of them ask you to stop doing anything. Instead they ask you to start doing things that increase the amount of pleasant time the two of you spend together. You're in control of initiating them, you're in control of continuing them. If you'd rather substitute another that is as small, and as much under your control and as regular and as mutually pleasant, by all means, give it a try.
Try it for a week, try it for two weeks and keep a diary of how things feel to you as the time goes on, about how you feel as you shift you concentration to carrying out this set of activities, small activities, that are under your control. If you have a little time, drop a note and let me know how things are progressing.