I agree that dissociation is very well possible, but also catatonia. Together with your lack of feeling it could be schizophrenia. You could have some borderline personality tendencies, but maybe not. With a lack of guilt, it is unlikely to be bipolar disorder (you could say that less or no (intense) feeling of guilt is what separates BP from SZ). I am in the middle (SZA/BP, sometimes called schizomania) and I think I generally feel quite a bit less guilt than most with BP (it does depend: post-mania depression is filled with it, mild depression as well). So when stable, I can be quite detached from my feelings.

It's a way of coping, largely subconscious and very much like dissociation (there are different types, but all seem to somehow protect you, but arguably not all).

Losing lots of time could be dissociation but also catatonia. These two are also sometimes quite similar, to make matters more complicated.

If you don't have (hypo)mania or depression, anything affective is unlikely. I would therefore say it could be schizophrenia.

However, it could also be a narcissistic or antisocial personality disorder. These aren't very common.