Postpartum depression can last longer than 7 months- don't put too much expectation on yourself to "just get over" it, for starters.
I've been on and off anti-depressant medication for the last secen or so years. The first time I started taking it, I was experiencing horrible panic and anxiety attacks at work, and I was convinced I was going to die. The doctor prescribed me Cipramil and Xanax and sent me away. Well, I took the Xanax once and that was enough for me. LOL. But I kept taking the Cipramil for another year, and it was a real relief. By that stage, a lot of things had changed in my life and I felt I was ready to live without it, so I just stopped, like you. Like you, I had my occasional moments of weepiness, but nothing major. I was off them for a year and felt fine the whole time.
Then I started getting panic attacks again, and after a while I went back (to a different doctor) and asked to be put back on the pills. I could see that all my depression had been building up again and I'd been ignoring it. She refused to prescribe me any medication- she said she made her patients go to counselling. So, I went to counselling and had no medication, and after a few months I felt better again.
One year after that, I dropped suddenly into the worst depression and anxiety I'd ever had- I could hardly function, and I got suicidal. I went to a third new doctor, who prescribed me Lexapro _and_ counselling. Well, he knew what he was talking about. The thing is, if you only take the medication, it's a band-aid. You don't address the underlying causes of your depression, and you don't get to understand them. At the same time, sometimes you just need the medication because your brain hormones (esp. seratonin) get so low that your body can't keep up with the demand.
OK, so- I'm nearly done with the essay

Here's what I've learned- medication alone is no good; counselling alone is no good. Medication and counselling together are the best approach. As part of that, you shouldn't just stop taking your medication unless you've really addressed the underlying causes of your depression. Otherwise you may well be taking them again in a year, wondering what went wrong.
I took the Lexapro for two more years, then decided to stop two years ago when we wanted to conceive. I stepped down off it gradually, going to a counsellor as I did, and this is now the longest I've gone without any help. I still have my moments, and I'm prepared to take medication again if I need to, but now I know ways to help myself and recognise the signs that my body isn't happy.
Go to a counsellor to talk it through, and if you do end up feeling sadder (or start getting headaches, which I did, or any other symptoms) don't be afraid to keep taking the medication for a while. It doesn't make you a weak person, or say anything about your life.