Dr. Beverly Crusher

"Look", they might say, "we have a woman doctor. Oh, and a female counsellor... uh, wait a minute... both 'caring professions'... I know, let's throw in a tough-as-nails female security officer!" And that's what they did, although the obligatory 'female in a male job' was eaten by a sentient oil slick early in the series' run.

Enter Dr. Crusher

Beverly Crusher, the Enterprise-D's Chief Medical Officer, has a History. Married to Jack Crusher, Captain Picard's closest friend, who died under his command, she is mother to Wesley Crusher, Picard's young acolyte. She also bears a torch for Picard that flies almost, but not quite, under his radar.

Played by Gates McFadden, Dr. Crusher is a caring yet no-nonsense medical professional. She's also feminine and strong, and has had a number of relationships during her tenure in Star Fleet, notably with a trill symbiot who, in the course of their romance, is forced to switch hosts, leaving its male host for a female one. (Dr. Crusher found herself unattracted to the being she loved when in female form and the relationship ended, albeit with good feelings on both sides.)

Crusher and Picard

It's unclear if Picard's feelings for Crusher are kept sublimated by the fact that she is his best friend's widow, that she's within his chain of command, or perhaps he just doesn't 'think about her that way'.

In an alternate timeline created by the trouble-making Q, Crusher and Picard have been married and divorced, with Beverly moving on to command a medical ship. In a quaint bit of Twentieth Century sensibility, she apparently took his surname when they married, so that fun could be had with the two of them both answering to the query "Captain Picard?"

Crusher and Wesley

As mom to the wunderkind Wesley, Beverly has her biggest challenge, but their relationship remained strong throughout the angsty-years. A scientist herself, she must have nurtured his scientific aspirations, and is rarely at a loss, except for the one 'warp bubble' experiment of Wesley's that runs amok, trapping her in another, shrinking universe from which her son must rescue her. I don't believe he was even grounded for the faux pas, however.

Interregnum

Dr. Crusher was briefly replaced as CMO on the Enterprise by the crusty and irritable Dr. Pulaski, loathed by fans for treating Data as a thing, and mispronouncing his name. Dr. Pulaski served throughout season two, and Dr. Crusher returned (from where? doing what?) in season three and remained throughout the rest of the series and into the ST:NG movies.