He is often mocked by his friends about his annoying habits of correcting people's grammar and avoiding straightforward dialogue when nervous.
He tries to convince his friends to act for the best in difficult situations, even though such actions may be difficult to carry out.
He does not learn he had been mistaken in thinking Rachel had sex with Mark until the following morning when he hears a message Rachel left on his answering machine, telling him she wants to work on the relationship.
The pair gets back together only to break up again when Rachel discovers Ross's indiscretion with Chloe.
These paranoias and insecurities often causes conflict in his relationships; for example, when Rachel began spending a lot of time with a co-worker of hers named Mark Robinson, out of paranoia he came to mistakenly suspect that she was having an affair, when in reality she only ever considered her relationship with Mark to be platonic.
She eventually becomes so fed up with Ross's jealousy that she announces that she wants to take a break from their relationship.
Also, he doesn't respond well when his parents don't give him the acknowledgment they always do and was clearly distraught over Jack's Porsche being given to Monica as a peace offering for ruining her childhood memories claiming that he was a "medical marvel." Ross is also perfectly comfortable with lying to his parents especially if it wouldn't tarnish the extremely high mantle they placed him on his entire life.
He framed Chandler for making him smoke marijuana in college and when this was revealed in "The One Where Ross Got High", he refused to tell Jack and Judy despite it being years and he had not done so since and once considered informing them in a letter simply out of sheer cowardice.
As he was the favored and academically gifted child who received the more credit and praise in comparison to Monica, he can't always be blamed for his sometimes enlarged ego.Ross's jealousy also becomes apparent during his relationship with Emily Waltham, when he fears that she is growing too close to Carol's lesbian partner, Susan Bunch.His jealous streak rears its ugly head again when he dates his student, Elizabeth Stevens, and ultimately accompanies her on her spring break vacation to ensure she does not stray.Rachel Green(wife)Emily Waltham(ex-wife)Carol Willick(ex-wife) Phoebe Buffay(make-out)Bonnie(ex-girlfriend)Charlie Wheeler(ex-girlfriend) Jill Green (ex-girlfriend)Mona(ex-girlfriend)Julie(ex-girlfriend)Joey Tribbiani Jr.(kissed) While he is smart, polite, caring, thoughtful and kind, Ross is often clumsy and socially awkward - taking the characteristics of the stereotypical "loser nerd".He is sometimes shown to have a good sense of humor.
He is angered when Phoebe asks him why he has this need for everyone to always agree with him.