Life is hard. You have to try to stick through the hard times as they DO often get better. Helper gave you some good advice. Could you also talk to a therapist. I also agree with hangman about the prescription maybe being needed of zoloft. This pent up anger could be life stuff but also a symptom of depression and anxiety.
Did you wean yourself off the Zoloft by deciding to do so by yourself or did you do that at the advice of a doctor? If the latter, then you should share these feelings with that doctor and ask his advice. If the former. then I suggest you tell your doctor what happened and find out when you could restart your prescription.
I think I probably relate to some extent, where things sort of get worse and it's getting away from you. I'd think of two things: (1) to have an outlet, like a punching bag in the gym or just running or some sort of exercise, or maybe it's venting to friends while you socialize with them in person and (2) where/when possible try to reflect on exactly where the problems lie.
Then, when you are calm, try to talk with your wife about communication perhaps, and try to get a a system in place for communicating.
Probably also to have your own thing going too, like working on yourself, maybe it's the gym, or a hobby or something like that, perhaps. Might make you feel more steady with yourself and that could also help with your relationship.
I'd also say it's great you have a wife! I know you know that, but just many of us don't, and many never will, or many are divorced etc. So that's an accomplishment and something amazing, you have each other, giving to each other.