It sounds like your recovery is suffering. I highly recommend reading Practical Programming for Strength Training by Dr. Kilgore and Mark Rippetoe. The information on energy systems, stress and recovery is very useful to help understand what is going on. So first some high points:
- A calorie deficit alone (diet) is enough to cause many people to be irritable. Combined with a heavy work load, it's a sure fire way to get people not to like you.
- You can get a lot of mileage out of 3 full body workouts a week with adequate rest in between.
- With heavy stress and inadequate recovery, cortisone levels rise, which is released from the adrenal glands (fight or flight). This may be a big contributor to what is going on.
I also am a software developer, and with proper planning you can alleviate some of the stress on the job. The trick is to get out of firefighter mode (always putting out fires), and be more proactive. If you aren't the one in charge of the schedule and negotiating with the client, that can be more difficult but not impossible.
Testosterone is an anabolic hormone, which means it is responsible for building up your system. It triggers growth hormone and insulin like growth hormone 1, which both are necessary to construct and rebuild muscle tissue. Cortisone is catabolic, which means it is responsible for tearing down dead tissue and making room for the anabolic processes to do their job.
The problem comes when the catabolic hormones are in higher proportion to the anabolic hormones. This can be due to over-training, inadequate recovery, or just general stress (cortisone is the stress hormone). When your body is in a state of predominant catabolism you can lose strength, become more irritable, and eventually have the symptoms of clinical depression.
Correcting a state of over-training is relatively simple. Essentially, you stop doing the activities that are pushing you over the edge. If you are facing motivation issues getting into the gym, take a break for a bit. If not, do some lower intensity work, and rehab related work. Focus on more recovery and less stress.
- Going too strict on a diet with a high work load is counter-productive. Find the right balance to help you lose weight, but still give you enough energy. Perhaps time your meals so you have the energy when you need it.
- Reduce the work load. I highly recommend at least looking at Wendler's 5-3-1 program for ideas. That's a 4 day a week program (but flexible enough to make it a 2-day or 3-day a week program) where you focus on a primary lift and add some assistance work, conditioning, and mobility. You can customize it to emphasize hypertrophy, strength, conditioning, or mobility--but all four components are still there.
- Try to keep your training sessions under 1.5 hours, with the ideal threshold less than 1 hour. When you use compound lifts like the overhead press, deadlift, bench press, and squat, you have the biggest testosterone response and helps the body remain more anabolic than catabolic.