Karen Read looks to be taking her retrial for murder in stride ... appearing relaxed after a recent court appearance -- having a drink and chatting with strangers.

TMZ has obtained photos of Read at SAVR, a bistro in Boston's Seaport District -- not long after she finished up another week of her retrial on Friday.

Eyewitnesses tell us Read was with her legal team -- including powerhouse defense attorney Alan Jackson ... who we're told flattered everyone in the bar, working the room and schmoozing like a pro.

The group, who was joined by Boston radio personality Greg Hill, was there for about an hour and a half ... and, Karen had an espresso martini or two -- just a little something to unwind after what must be a difficult couple of weeks for her.

We're told she didn't do anything rowdy, keeping mostly to herself -- though she wasn't standoffish either. Several groups approached her and asked for a pic with her and her lawyers, and we're told she obliged them all.

KR did chat with a couple people outside the group, our sources say ... and, overall, her mood seems upbeat.

As you know ... Karen is charged with second-degree murder, vehicular manslaughter while driving under the influence and leaving the scene of a collision causing death after prosecutors claim she ran over her boyfriend, Boston Police Officer John O’Keefe.

Read's lawyers have fired back by claiming she's the victim of a cover-up by law enforcement officers who she alleges beat up O'Keefe at a party and threw him out in the snow where he died.

She was tried last summer ... where a jury voted in favor of acquittal -- 12-0 -- on both the second-degree murder charge and the charge of leaving the scene of an accident where there was injury or death. They did vote 9-3 in favor of conviction in regards to the vehicular manslaughter charge.

The lead-up to Read's legal trial has already led to some explosive moments ... including one where key witness Kerry Roberts admitted she didn't actually hear Karen Read ask Jennifer McCabe to search Google about hypothermia just before the three women found O'Keefe dead, despite previous testimony.