Need some Advice

Hello , this is actually my first time ever posting in this therefore I'm sorry if I haven't used this group correctly or even if this is the correct group to post in about it but I kind of needed to let it all out and I guess this is where I've ended up and hopefully I can get a little help about it from some of you guys .

I'm 19 Years old and my partner is 26 years old we've known one another for about 5 years now and we've been together for just under a year . During the 5 years my partner befriended a woman I've near really seen eye to eye with because of how she is has a parent to her little one and her life style .

My partner and me lived two very different lifestyles over the first four years , I was in work or in college while he was in uni and party etc , But since last year and a little of 2016 he's ways changed and he's now left the party lifestyle behind .

But his friends won't respect that he's in a relationship and won't respect that he's changed his ways because he's grown up in a way since then and for them disliking me and trying to cause problems between him and I its ended up us not hanging out with them and him just speaking to them every now and then .

But this one particular friend of his just keeps disrespecting our relationship and keeps trying to get him to come to hers for a night alone and tried to get him to flirt etc back to her but he hasn't .

I basically had enough of it a few nights ago and told her to stop trying to be in mine and his relationship / drinking and taking drugs and pay more attention to her child and be a parent .

Which I will admit wasn't my place to say but I can truly say it did feel good getting it off my chest and I will always stand by what I said , But now she's sending me death threats which I kind of expected to happen because that's the type of person she is ( doesn't get her own way or hears the truth she will act like a 5 year old ) . I'm not worried about that but what gets me is my boyfriend says to me I was in the right but to this girls mother hell say I was in the wrong .

I've told him I was annoyed at him for saying that which leads to him ignoring her now for how long I don't know but honestly I need some help but after all that drama I've felt emotionally and physically drain and I don't know if its because of the crap she's making up about me online to get people to bully me or the lack of support or just my depression .

I can barely sleep , its 5.30 am and here I am writing this when I should be asleep but I can't for some reason , my mind is working over time , I know no one will probably see this but I guess I just need to get that all off my chest and maybe hear some advice and opinions ....

Thank you for reading this and Good morning or good night :)