Re: How do you deal with.....
for me it's as for Krystal, only more on beginner's level - I constantly swear and draw angry faces because there are so many things that don't turn out as they should. Most of my dojo mates became familiar with "Scheiße!" and "Hasssiktir!", which are the appropriate exclamations in these circumstances for me. And yes, it happened also that I got the impression one or the other uke thought the abuse was directed at him, and it happened more than one time that I apologised and said, no, it was directed at myself, at the technique and at aikido as such.
I wouldn't think too much of it if I were you. Not everyone has the same temper and patience. We accept to be confronted with our own inadequateness at every single training lesson; some take it with Christian humility or zen attitude, and some others are exasperated and angry. I very rarely saw people taking it out against their training partner. If you are somewhere in the middling kyu ranks, you are used to white belts grasping the concepts very slowly, and you are still used to grasping very slowly yourself. So sometimes something goes wrong, and you swear like "fucking hell!" or anything else that slips out easily and provides an adequate non-violent outlet for your wrath - but without any bad intention in most cases.
All the best,