I have no friends.

I have no friends other than my boyfriend and it's really starting to get me down. 
At school I hung out with a few people, but I always seemed to be the target of their 'banter' which actually got me down, when I met my boyfriend I started hanging out with him because the people I was hanging out with were horrible. 
At college I met a few people who I did a lot of stuff with (2 years ago this was) and now at uni, I just stay civil with them apart from one girl who is my only friend. But now it's summer we haven't spoken once, I think it's because she has a new boyfriend. 
My boyfriend is going away for 10 days on Saturday and I don't know how to cope because I have no one to hang out with or do anything with. We argue when he hangs out with his mates but it's because I'm jealous and I have ago at him because he's actually out doing something whereas I'm at home doing nothing.
My mum says I need to make friends, - I have to dog sit on Saturday night but I have no one to invite over. Then everyone from work invited me out Saturday, for the first time I'm actually being invited out somewhere but I have to dog sit. I'm trying to convince my mum. 
I'm getting really down about this right now, what do I do 😪