Find something you love doing ....
For me, it was weight training.
For others, it might be yoga ... might be other group classes.
Take advantage of all of the programs your gym offers, until you find something that keeps you comin' back for more.
Keeping fit & active shouldn't be a chore, nor should it be something you're not looking forward to!
Years ago, I took up squash, and joined a womans' only league ..
Keep an open mind, and try it all