Hello and welcome.
Just thought I would fill you in on some of my favourite treats, might help you with some ideas.
My fav low fat treats are:
Creme caramel deserts-0.9g of fat per tub. (Sainsburys brand)
Pink and whites-marshmallow in-between wafer.
Weight watchers caramel crunch desert (my fav) 2.6g-watch out for other WW desserts as they tend to be rather high,they work on saturated fat,not total fat!!
Ben and Jerry's do a cherry frozen yogurt,it's not low low fat but much better than ice cream, I have a small cone (trace fat) fill it with mini marshmallows (fat free) and that way I only have one scoop of frozen yogurt which is low in fat!
I also buy organic apple and plum pure^ and stir through fat free yoghurt.
Marks and spencer do a fantastic 'count on us...' double chocolate sundae for the chocoholics. It's is 2.6g of fat per 100g and the tub is 130g. 182 calories per pot.
M&S also do a good 'count on us ..' strawberry trifle. Not sure on exact fat figures but I know they are good and well within the limit.
Savouries
Weight watches hoola hoops (0.2g) per 20g bag.
Snack a jax - all flavours.
Be good for u crisps from sainsburys- tai sweet chilli or cheddar and red onion (1.5g) per bag.
Certain packs of Japanese rice crackers are good. Make sure you look at the label coz there can be big differences as some have lots of peanuts, therefore , higher fat content.
It just takes time to shop and going to different shops is helpful as u find different things. I'm still learning everyday.
Also got a useful BBC good food 101 low fat feasts recipe book. Nice meals and all fat and calorie content per portion is stated. Good if you cook from scratch and have a partner that is supportive. My partner is loving the low fat meals and treats! I just make him a good lunch for work that contains more fat and calories so that he gets more than 30g of fat a day and more calories.
Best of luck.