what can I do when she acts like a stray?

Last october we adopted a stray cat.
At first I couldn't even get close to her but as time went by we've made amazing progress.
I can pick her up, play with her, pet her, she is comfortable at home, she's even learned her name (sheebah ) etc.
Its all fantastic! she's become a very special addition to our family.
I have to thank everyone from this forum since I've learned how to bond and treat her by reading countless posts over here.

Here's the problem:
Every once in a while she acts "freaky". I know its normal considering she lost trust in humans but I wish I could do something to help her more. I feel like all the things I've done have made her progress until "this point" but I need tips to help her progress even more.

She acts like a stray cat when she's eating. If she's eating and I come close or if she hears footsteps she'll run for her life! I think she thinks I'm going to yell at her or something (which is far from true). If I know she's eating and I have to get close to her (for whatever reason) I try to walk slow and sort of act as if I'm not looking at her.. it helps a little but not enough because she still gets very scared.

When she's inside our home she has no problem with me petting her but if we are outside (in our backyard) she starts acting like a stray cat again. She gets scared if I aproach her.

There are other issues too, in general the main problem is that sometimes, out of the blue, she acts like a stray cat again and I would like to know if anyone here has had a similar experience or if you have any advice on how I can help her.
.. or if someone could help me figure out why she goes back to "feeling like a stray cat"?

You didn't mention any names, but after looking at your signature pics, I would guess that you are talking about Mofy? (just curious, she has that look in her eyes)

I have 1 boy like that in my home and he acts like this randomly. All of mine were born feral and I treat them for the most part the same. But for some reason, Oscar gets scared for no obvious reason. Eightball does this to a lesser degree.

My theory is that some cats are just more skittish than others. I have learned to take cues from their postures and when they either get that look in their eye, or their body takes on the freeze pose before flight, I simply back off, get myself on their level (sit down, etc) and talk calmly to them. If they show signs of relaxing, I reward them with lots of scritches. I also have to question myself on the importance of them being the perfectly sociable cat at all times. I don't set expectations that they can be, therefore I accept them for what they do.

Your girl's outside behavior would have me a bit concerned. If she is frightened and takes flight, do you have the area confined so that she can't run away? It's one thing for them to run under a bed. It's another for them to run up a tree or leap over a fence. I would suggest harnassing her outside and give her positive attention or treats when she is with you. You want to relate outside with positive experiences that involve you.

The very first kitty we rescued was very young. He's five now. When there's a loud noise (we drop something or have a loud cough), he bolts. He hides when anyone comes over. Even our formerly abused kitty has accepted Gary's mom as part of the family she can trust. Lazlo still hides for 2 - 3 days when she comes to visit. Yet this same kitty lies on our laps for brushes, rolls on his back when we pet him (though he does NOT want belly rubs!), and sleeps in bed with us.

Some kitties are just more skittish than others.

Our kitties free feed, but we give them a wet meal every evening. I have to be sure we're done in the kitchen for a good half hour, because ANYTHING we do in there when they're eating will cause Lazlo to bolt. And when he was a kitten outside, the only time we could approach him and pet him was when he was eating! Strange turn of events, but there it is. And while it only takes them about 5 minutes to eat, Laz gets skittish, won't finish, so goes back. So we give them a half hour so Laz can eat a little, leave, come back, eat some more, &etc. If we need ice or something during that time? Too bad for us.

Laurie