Oh no, I've not been in here for a while, and just seen this and your other thread
OK - one option (and granted, it's a bit of a big leap, but stay with me!) would be to go back and study anyway: I know you said you have a record that stopped you with nursing, but why not have a look at some other area that might not be as strict over the DBS thing, and have a think about university? I'm not saying it will be easy - it won't - but you will have access to a wider range of support, through the university, and you will also have the chance to meet many more people, and be involved in a wide range of activities. Plus, there will be a student support service for MH, and unlike the NHS, they can't tell you to fuck off - so you will get the help you deserve. It will probably be hard work for the first little bit, but then, you probably won't look back. The only kind of offence that can stop you being taken on by a university is being a category one sex offender, and even then, it's all looked at on a case by case basis.
I work at a university, and we have a lot of students with MH and other issues, across the whole spectrum of possibilities, and I think we do a really good job of supporting them. In my own experience, we've never had a student that has MH issues fail to get their degree (and people sometimes do) - sometimes, it takes them an extra year or they need some extra support: but that's not the end of the world - after all, people with SEN need some extra support too. It's about levelling the playing field, not giving you an advantage, and it really might change your life and give you more opportunities. I'd recommend choosing a newer university- one of the former polys - because it's my experience that these post-92 institutions do a much better job of pastoral support in more complex cases (like yours seems to be) than the old universities, but pick somewhere you think you'd like to go. It's not too late for next year, either - you can get a place to study in 2016 as late as clearing (A level results day on, so August) or even September in some cases.
As for the man question: I think the problem is really, when we're lonely, we tend to make worse decisions - I know the shittest relationship I ever had was were it was two lonely people getting together, not because we were inherently compatible but more, "Hey, I'm lonely, you're lonely: match made in heaven!" So it can cloud the issue, because we get so desperate for someone to give us a hug that we don't care if they're Mr/Miss Right - just that they are Mr/Miss Right Now. And that's fine as long as it works, but once it stops, it actually ends up making things worse, and almost becomes some kind of self-fulfilling prophesy: I'm so shit, no-one wants to be with me, and I hate myself, so it's no surprise no-one else likes me, and anyway, I am shit at relationships etc etc So we just get taken advantage of because we're needy and available - which puts decent people off, but acts like catnip to a Persian on someone else who is also needy and available, or someone who is fundamentally bad and manipulative, and targets vulnerable people like this.
(I realise this isn't an answer for you: but I am trying to explain why professionals are saying that it's not the solution.) I recently told my psych that I wasn't involved with anyone at the moment (I haven't dated for years, but had a sort of substitute type thing going on) because I figured I needed to get well first, so I could find the right sort of person. He was dead chuffed with this, so I guess he sees it as an improvement I'm not suggesting you should do the same - but it might be worthwhile trying to investigate the men you are interested in/are interested in you, and assess whether they have problems of their own (no disrespect to anyone here - but you've got your own problems, as do I, and that takes a lot of emotional energy to deal with, and doesn't leave a lot of space for handling someone else: that's not being selfish, just acknowledging that there are only so many hours in a day, and that if you're not putting the emphasis on trying to hold things together for yourself, you risk getting more ill as a result) and how serious they are (so I would be fine, say, to be with someone with certain issues, but someone with addictions would be difficult for me, because I already struggle with debt and poor impulse control etc).
You then need to examine him against your benchmark of what a good guy looks like - it's not about having a check list of Mr Perfect, but more thinking about the kind of things that might be a problem. So personally, I wouldn't want to be with someone who is recently separated, as I think their head isn't in the right place and they are still grieving their ex, say.
If there are no red flags - you're good to go. But if there are things you are explaining away - "Oh yes, he's like this, BUT x y z" then run: because he's not the right guy for you but the loneliness is taking over: does that make sense? There's no reason you can't find someone great - but you need to make sure that you're not sabotaging your efforts, even whilst not meaning to.
PP have made some good suggestions about alternatives to MIND - I guess they must be very brief-intervention type in their groups: have you had a google for specific MH diagnosis sites/forums, and seen if there's anything specific for you (I think you said you have BPD, but excuse me if I've not remembered that correctly)? Also, might be worth pursuing private therapy again - I know it went horrible at the end with your previous therapist, but there will be someone out there more suitable for you. Inter-personal therapy might be worth looking into, or maybe something psycho-dynamic, as you said past events are dominating your thoughts. Also maybe schema therapy might be appropriate, depending on your history? Have a play on Google, and see who's in your area - plus, some people will use Skype - not ideal, I know, but worthwhile if you can't find the specialist you want.
Sorry for the long post, anyway, and sorry you're ill - hope you'll be feeling better soon: and remember, you're not attention seeking for being ill - you can't help it, and should be praised for being proactive enough to try to find help, despite all the obstacles placed in your way!