Me too. Married at 24, separated and went to live elsewhere at 28, formally divorced at 30.
Also, to answer your other question, I married with the feeling that the relationship wasn't 'right'. There were various reasons why I did what I did, not worth mentioning now. I admit, it was a stupid thing to do and I made a mistake. HOWEVER, if it helps, my thinking later on was like this: ok, I've made a mistake. But I'm not going to let this mistake to destroy my whole future life, am I? Very simple.
If you're unhappy and things are not right - leave. There's absolutely no point and no need to stay together 'just because'. Your marriage didn't work out and that's it, it happens. Doesn't matter, if you're in your 20s, 30s, or any other age.
As for other people... Some won't care, some will support you, some will judge. It doesn't matter, really. It's YOUR life, not theirs. They won't have to live with your husband in an unhappy relationship - YOU will. Don't let anybody guilt-trip you into staying and 'making things work', if you don't want to.