Hey
Let me take a different tack...
Maybe it is HOW you are incorporating their advice and or suggestions? For example, if I post my lyrics and someone comes back with a suggestion for a perceived issue, if I incorporate their suggestion more or less as is! I guess I would feel as you do.
if however I look at the problem they found, so I learn to recognise similar before posting next time, I have learnt. If I look at the mechanism they used to solve it I have learnt... If not I talk to them to get to the gist of why what they suggested would work? lastly, I try applying that mechanism or similar to the current problem and write my own words. that way the song is still true to me.
Only occasionally have I found that the contributed lines were so good that my lives are just crap by comparison and nothing will do but those lines. It then comes to a 3 way choice: use their lines, use my not quite so good lines or keep the imperfect original.
You can head that situation off in some way by limiting the help you get by stating what help you do not want in your original post. That has consequences in that you will maybe get less feedback, some people will tell you what they want anyway, while on a positive side the help you get tends to be more focused.
I get you don't want to be spoon fed. Great, me too. But you can still pretty well get the help and sleep peacefully at night.
Cheers
john