Im honestly not 100% sure, but I can give you a little personal insight about steroids and emotional swings. Thinking about it, I dont think this theory would be a hard rule. Some "dry" steroids are very powerful and can cause some major aggression, especially if you are prone. With any steroid, unstable hormone levels are probably going to cause more issues than anything else. I find that consistancy is the key, with just about all of the side effects I suffer from. Making sure that you keep doses stable will require understanding the halflife of the steroid you choose to use. Even if you want to use any of the various DHT based drugs, test is the primary base of any cycle, so you'd want to learn how you deal with it first. Once you understand how test works in your body, you can consider adding in other gear to your cycles. If emotional problems are a concern, there are steroids I'd avoid. Tren, Halo and EQ may cause problems. That being said, steroids generally magnify your feelings. If you are prone to having a harder time controling your emotions, there is a high chance that steroids are going to make that worse. In this case, you would ideally deal with these problems before you cycled. There are few ecceptions I'd make to small cycles that wouldn't require using test as a base. The main compound that comes to mind is anavar. Anavar is a mild steroid and the side effects are pretty mild too. You can gain a hell of a lot of strength from it though and with strength can come muscle gain, if you are eating properly. A standard dose would be around 50mg ED for a male, and you could run this cycle for 6-8 wks, followed by PCT. 

PCT drugs are related to estrogen and these can also cause emotional swings. I would choose nolvadex over clomind, as nolva has fewer sides of this nature for most people I've worked with. Keep in mind that PCT can be an emotional rollar coaster for the most stable of people and no matter how you deal with things on cycle, this is where you would probably be more likely to suffer. I would think long and hard before starting a cycle if you are having emotional problems, because i can pretty much promise you that PCT will suck emotionally! I'm not telling you not to do a cycle. Just be responsible and make a responsible decission. 

Another direction to consider is peptides. igf 1 lr3 can give you some decent, keepable gains without messing with your test/estrogen levels.