Hi YG, just wanted to send you my support. As some of the others have said I think it would have been abnormal NOT to have had some sort of meltdown after all you've been through.
I know its not the same as the death of your spouse, but I had a similar experience 9 months after ExH and I separated after 15 years of marriage. Initially I was very "gung ho", and determined to get through it. Then I started experiencing the anxiety symptoms you describe, and was obviously becoming depressed. I began ad's and took 6 weeks off work. It definately helped. The current advice is to stay on ad's for 6 months after you start feeling better. Also it took 2-3 weeks before the meds kicked in, and during that time I had some side effects (worsening panic attacks and feeling very tired). But once they kicked in the ad's definitely helped, as did having time away from a stressful job.
Be kind to yourself, and give yourself more time. Its only 10 months. Sending you lots of love xxx (we met a Sheffield spa in September, if you want to CAT me, some one to chat to, you're very welcome)