when your always putting aside your own feelings for someone else.
when you always do what the other person wants and not the things that make you happy.
when your always trying to fix all the things that go wrong and they put no effort into it.

When you are giving more than you receive. When the other person has no empathy. When you wake up feeling like something is "wrong".

OMG we had the same Idea, Mind meld.

When a little voice in the back of your head screams WTF?

Not asking your opinion anymore.
Disregarding your feelings.
Backing off in the sexual activity department.
When it becomes, "But, what about me and what I want?"
When he considers you more like his mother than his wife and lover.
When he makes plans for leaving behing your back.
Communication is at a minimum.
Your needs are not as important as theirs.

Oh, Courier you said it best, but here's my contribution - when he thinks or acts like he is your rescuer or knight in shining armor. There was a discussion re this in the abuse community ;-)

if it doesn't feel right, then it's a red flag, nip it now.

Great topic...
When you find yourself making excuses for their behaviour or thinking if you just love them enough it'll be ok....
Or when that little feeling at the back of your neck ( or your gut or whatever your personal fright barometer is) tells you something is wrong---IT USUALLY IS! God put that there for a reason--listen to it!!
Uh...would you like your daughter or son to date someone like this person???
oh and Egg shells--walking on them for extented periods of time is bad for both the "sole" AND the "soul".
(Bad pun I know--but true.)

What's the knight in shining armor thing? My stbx was doing that too.

As far as the "intimacy" thing goes... I have to admit I was the one who backed off. There was something weird about how he was being and it turned me off. Also, emotionally I was so drained and it was so hard to be intimate when I was so unhappy with him emotionally. Does this mean I made things worse?

Emotional and mental abuse make it very hard to be intimate with the person that inflicts it. The abuse breaks the trust.

when they start to isolate you from everyone in your life finding fault with everyone and putting them all down and pointing out thier faults so that soon you have noone to laen on except him your abuser.

when they go over their text message limits and never have before (be sure to find out why)

Hiding everything - mail, financial stuff, password access to computer, way too neat/organized, breaking commitments, erasing cell phone calls, getting a lot of restricted or unknown calls, leaving the room to talk on phone often, can't be reached by phone because of reception or my call didn't come through (couldn't use the one I'm reading a lot about phone broken because he needed it for work) and never meeting all of these "friends" he talked about so much....I'll think of more

doing all the " work " in the relationship, feeling invisable and taken for granted. You gut being in knots because you just know it's not right. Not being able to talk without tearing up because you've held everything in for so long, being ashamed and looking for an escape route.