Witout knowing the type of anti d you've taking it's hard to tell whether or not your doctor is making the right more. There's advances in anti d's constantly happening, and new information.
Also different SSRIs work differnetly. Generally the body will become use to them rapidly, when compared to other forms of anti d's. Have you talked about trying a different medication? Also do you attend any therapy, SSRI's are often only effective when joined with additional external support. Also, it's rather common to be given other medications depending on your condition to help with other areas, such as panic, sleep, and more.
I've been on anti's for over 10 years now, and anti psychotics, as well as a mixed of sleeping tablets. Most of the time to notice any effect I have have to take a mixture, which often needs changing or increasing within 6 weeks to about 4 months. They don't really help me function like a normal person, but they make me function more like what society would class as normal. A lot of the time when taking them I often loose something else which I regard as important. Some have affected my creativity, or my excitment levels, or even orgasm, and some have made me able to cope but act very grumpy. Then there's other side effects such as weight gain, loss, hair loss, gittery movements, and more. I've found that most of the tablets work best when I either attend therapy, or find another activity I can focus on too. I personally found running a good way of helping as it made me focus on something else other than my mood and the medication. When focusing on the medication I found it less effective, as I would worry about it more. I know it's tricky to try and for get, esp when you have to take it at least once a day, but otherwise you're just letting it control your life.
Sometimes I go through phases without them at all, and I think this is healthy to take a break, and let your body try and adjust to its normal hormone levels. Yet, I know personally and from the people around me, this isn't the best thing for me. As when I don't take them at all, after one or two days, I can't cope. I can't leave the house, I panic, I try and be ok, and even running or exercise doesn't help. I know I can't function without them at all, and I personally hate this. I'd love to beable to be ok without them, and I spent years ignoring the doctors when they said I needed them as I felt I knew best.
The fact is though, even when taking these tablets, I don't become happy. And actually I don't expect I will become happy through taking them. Depression to me isn't about feeling one extreme emotion or another. Without tablets I act and seem down, and can't cope, but I can't really feel whther I'm sad. Tablets generally just help me know what I'm feeling so I can cope with these feelings. So I can control them, and stop them from becoming over bearing. And personally if a tablet caused happiness all the time I'd become a little scared of it, as I like being able to feel the negative and positive emotions.
If the tablets have started to make you happy that's good, and what your doctor is doing may be right for you. Try not to worry too much about coming off them, just seem where it goes. If you worry too much, you'll porobably become depressed about it and form another negative thought pattern, which'll just take time to climb out of again. This is also why it's important to have support from therapy or a similar network, to try and help you get out of negative thoughts, etc.
Maybe, reward yourself with something like an activity. Go to the movies once or twice a week, or go out with friends, or similar. An activity which you'll find enjoyable and be able to focus on whilst you are going through this change.
Sorry for rambling i'm not sure if any of that made much sense really. But personally, if I was able to cope without meds it would be wonderful, not having that restriction on my life and extra chore of either taking them or measuring out liquids.