My question is: in sentences like
1) I can't get over seeing my ex-wife with her new husband.
2) The coach could'nt get over losing the state championship 47 to 0.
3) I can't get over the way you look - you've lost so much weight!
what's the meaning of this "get over"? Does it mean "to tolerate" or something such as "I can't believe my eyes!". I cannot understand it.
Thank you all for your help.

