Hi, I'm new to well posting in here. Your simple thread title caught my attention so I thought I Would add my experiences here as well perhaps what may be some insight. I can't say if I am right only that to me it makes sense. So here goes...
I have for many years done what you describe. I generally recall my dreams that cause the tears and , hmmm. they really aren't as simple as tears I wake myself up gasping in those kind of take your breath sucking in sobs, or sometimes just a very drenched pillow and the knowledge that I Have been crying my heart out. For me I know PTSD is an issue and I won't get into all that for now.
First yes , its so disconcerting. I wake disoriented half lost in the dream. The hard part is that most of the dreams are actual events that took place and sometimes just an extension of an event I remember. I sometimes grope to get myself reoriented to the year, my age, where I live etc..
Now my hypothesis, there is some evidence that at least part of dreaming is an undoing of the days events, reliving through the night so that when we wake up we are free of the things done the day before. I believe this. then there is this part that is just my opinion. In life I do not cry much for what has been or even more what is. Stuffing all that stuff has to have an outlet. tears are cleansing to the heart. Now I am not convinced that the really hard sobbing is that , I do not know. I do think that what I will not do in waking my heart/mind is trying to get out when I am asleep so that I have in essence cried for what is or was/wasn't.
I have had severe chronic pain from well over 30 plus jaw surgeries alone not to mention things like uterine cancer, an auto accident that nearly took my life and so on. Some of the dreams are all that hurt and yes even physical pain that causes the tears so for me its a bit complex.
Perhaps if U can look closer at what in life U are not letting out in the day U may find that the tears lessen. Giving ourselves the right to cry and seeing that even if our tears did no good when we shed them say younger they can be and should be heard by us to give recognition to our hurts and the right to be happy, loved etc...
I hope this helps. anyone have any other ideas or professional experience on this one I would be most interested in hearing it.
Be well and sweet sleep in the nights ahead.
Willoe