Hi, Alice,
I have pulsatile tinnitus in only one ear (right ear), too. For most of us, it isn't really worse at night; it's just that you can hear it more lying down, with no distractions around you. The pulsating sounds certainly make it difficult to get to sleep every night.
What works best for me is lying with my good ear facing down on the pillow so that I'm less aware of the pulsating. Also, I take two (2) Magnesium Chloride tablets every night about one hour before bedtime. It doesn't really help with the pulsating, but it does help me relax and fall asleep naturally. I've tried masking sounds in the bedroom, but that doesn't seem to work very well for me because I am still conscious of the pulsating.
Also, I've heard from some other people with pulsatile tinnitus who say it works to put an earplug in the pulsating ear at night. That doesn't work for me, but you could try it and see if it makes any difference to you. I'd suggest using the soft foam type of earplug for that purpose.
Good luck, and I hope some of these suggestions will help you. If these don't work, you could try a prescription sleep aid or anti-anxiety pill about an hour before bedtime.
Best wishes,
Karen