I'm pretty close to my family, but only talk once every week or two. It's just so hard to find a mutual time. We email in between with quick "I was thinking about...." or "I thought of you today when...." which helps me feel connected.
It's been interesting how different people respond to different modes of communication. I realized that I really don't like talking on the phone much at all, but prefer email. Matter of fact, one brother, whom I love dearly but rarely spoke with before we moved over here, has started a really wonderful and thoughtful email correspondence with me. I love it!
I was thinking about starting another thread on this for a while, but I have been really disappointed in my friends - they rarely write or call. I am starting to get perspective on that - that just because my life has slowed down, theirs hasn't. And when we do talk, it is clear that they think of me often and miss me. But I have been here 4 mos, and my friends have written maybe 2-3 times! People I checked in with every day! And one of our circle is dying of cancer, and they still don't check in. It is frustrating.
I'm sure your pregnancy is influencing your mom's neediness. Does she have email? Would it help to email her updates on your pregnancy (and then the baby, because it may get even more intense after the tyke arrives)? No guilt. Motherhood brings plenty of that. No need to heap it on from elsewhere.