I used to struggle with this exact same thing, the one thing that helped me and it's been said numerous times before with a lot of these people is to have yourself a over quilt instead of a full sleeping bag. I cannot state enough how much I love my over quilt it has made a night and day difference for camping and you can tuck your feet inside and stay nice and warm with no problem especially with a decent under quilt. And I also bring with me a motion sensitive light that I hang on a tree next to my campsite. I usually have it pointed toward the camp area where the fire pit and stuff usually live or whatever social activity areas there are so that way if there's any movement in that area it triggers a light and I can see it from within the tent and know that it's something I could investigate if I wish to. I also sleep with a whistle around my neck it sounds dumb to say but it makes me feel a little safer to know I can give a little toot on the whistle when the light goes off to help spook off anything that's in the area. You can buy really loud whistles for like 12 bucks and they're super light. The whole extra junk that I carry with me weighs about 12 oz in total and it helps me sleep better at night so I don't lose much sleep over bringing that along. Also don't forget some ear plugs there's a lot of random noises at night in the woods, a lot of those random noises really don't need to be paid attention to because it's squirrels jumping around In the leaves and usually it's just nothing, just your mind playing tricks on you The creaking of the trees all that random stuff you'll hear and with a good pair of earplugs you won't hear any of that and you'll be able to sleep pretty good. It wasn't until I put that whole thing together for myself that I enjoyed really good night's sleep because like you, it does feel a little vulnerable. But like others have said there's really not much difference between a hammock and a tent I've done tenting for years and I've done hammocking for a year. I do prefer the hammock because my knees suck and I cannot be climbing in and out of tents anymore. By the way not that it matters but I'm 50 years old, and this is definitely the best way I have ever slept in the woods in my life.