Well the ex girlfriend thing, I think that would be kind of normal for most people. Going through breakups is hard, moving on is hard, and can be depressing. I think that's situational depression, when you have dealt with it and have moved on, gone through all the grief and acceptance stages that come with ending a relationship, the depression you feel about it would also pass.

The mood in Bipolar can change for no reason, but probably more often than not there are triggers that happen that help push the mood along, or start the switch in the first place. Good example would be your getting a job. Most people would feel excited about this, and maybe even stressed. But if you go way beyond normal excitement and move into hypomanic symptoms, then it could be looked at as a trigger.

A person can have lots of triggers, some of the most common are stress, sleep, abrupt changes, breaking routine..., even something good happening. This is going to be personal to the individual.

How long did you feel hypomanic for when this happened? How long do you feel depressed for when you think of your ex?

Knowing your triggers can be good, not to avoid them altogether cause that's impossible and limiting, but learning how to minimize effects they may have on you I think is the goal. The thing with bipolar is that even though these things that happen in life are normal, and reacting to them is normal, the intensity of how we feel it is probably intensified a lot.

Like say, I have a lot of stuff going on in my life right now, nothing bad, but lots of change, that makes me feel stressed, the stress makes me sleep less, the lack of sleep cause me to start getting manic, I recognize the mania and look for the triggers, try to cope with the stress better, get my sleep back to normal, and keep practicing self care ( meds, exercise, whatever you do for this etc ).. I might be able to bring this back to a stable point.