I want to leave thank you message to someone, who was in our laboratory but out of our lab slight after I joined the lab.
Now she came back, but this time I am leaving. So...
"Hi Nasrin. Though we haven't spent much time together in the group, I can't forget your kind help when I joined the lab.
Hope everything around you goes well and lots of pleasant events come to you. Thanks!"
Does this seem...awkward?
Not at all. It sounds fine to me.