Well everyone, am a scorpio in too many houses to mention, and just married a cancer male after 4 years seeing each other, so here's my take. . .
Yes, they wear their heart on their sleeve, are moody and can withdraw for days. BUT - they are fiercely loyal and dedicated to a relationship too. my cancer male is highly intelligent, handsome as hell, and has no commitment issues at all. maybe the fact that we've both had long term relationships before makes a difference, or that we are older (50's) and know what we want - I don't know. But he's been fabulous. Not afraid of talking things out, and holds no grudges. We get mad, spout off steam and get over it. The fact that we both use humor to get us thru tough times is a godsend too. Our relationship has been tested to the max (ER visits, problems with ex's, house fires, etc.), and we just got closer thru it all. I like the loyalty and the the fact that we are both willing to work at the relationship. Of course, I could do without the stubbornness. But he is also compassionate and strong. We are both RN's and work in a psych setting, so I've seen both sides. And he doesn't seem to mind my intensity.
All that said, I think you have to use this astro stuff as a guideline, not a hard and fast rule. If you have the same basic ethics and moral principles, it can work. It all boils down to what's really important to you both. For us it's family and keeping each other happy and on an even keel. It aint easy, but it is ultimately SO worth it. Don't dismiss anyone out of hand because of their sign, just know what your dealing with and TALK about it. My Cancer male is the best thing that ever happened to me.