Emotions are the difference between a boring roleplayer and one everyone wants to roleplay with.

While sentence structure is very important (varied length, proper punctuation, no run-on sentences, etc), using the same emotion words gets boring.

What looks better?

He felt happy while he watched his girlfriend walk beside him. He would feel sad if anything happened to her.

Or

Joy lit up his gaze as he watched his girlfriend stroll beside him. His heart would have been torn to pieces if anything happened to her.

What To Remember
[This also applies when writing books]

• If you ever have to use boring words [see, happy, sad, walk, etc], I suggest Thesaurus.com or just look up synonyms.

• Keep it varied. Using the same word to begin a sentece twice in a row is a taboo (unless trying something with assonance), and try to never have the same beginning word in a single paragraph.

• Run on sentences are very boring and confusing to read because your eyes get tired and it's hard to keep up with all of the various parts of the sentence especially when there's no commas, dashes or semicolons.