Whenever I grow too attached to or dependent on a friend/loved one I do *anything* for them. I go miles out of my way to do favours for them or help them out. Because at that point, they become way more important than I am to myself. I say "it's fine" when they don't for example pay me back for something, ask me to do something that hugely inconveniences me to help them, I brush it off even though inside, it really isn't fine. I just don't notice it at the time if I'm hugely emotionally invested in them. But it feels impossible for me to argue or set boundaries because I don't want to upset them or lose them, even when I begin to recognise that I'm being taken advantage of or that I'm being treated like a literal doormat.

This starts becoming a huge issue at this stage where I *still* can't help but inconvenience myself hugely to do things for them (it's reflexive by now) but I've lost enough of the emotional dependency so that I'm slowly able to feel resentment and anger at them.

I spent most of today (that's hours) scouring the city I live in looking for some stuff my friend (I guess FP) needs to buy but which can't find where they live. I bought them and I messaged my friend the prices but the conversion rates etc means even if they pay me back in whole I'll be losing a few dollars here and there. Normally, it really won't be such a big deal. Except the debts from all the favours/small things have built hugely since they've become my FP to now (I'm talking like, hundreds of dollars). And that all the small things over time which were mostly my fault (letting myself be stepped over and brushing it off and doing anything and everything for them) are building up and *now* I'm aware of them. I don't want to hate my friend, I really don't. I don't want to lash out at them. I'm probably not going to since I'm too terrified of getting angry at people to do so. But this pattern has happened before; the resentment builds until I can no longer be their friend or close to them and it hurts both of us. I'm so internally angry right now though and I have no idea what to do about it. And I *still* can't help but continue to say yes to everything my friend asks. 

I don't want this pattern to repeat again and again which it has all through my past. But I don't really know how to fix it. If I can never stand up for myself or say no or set the right boundaries I'll always end up over extending myself for one person I'm dependent on, too scared of conflict and their anger to say anything, and then grow to resent them and during that period also have spent an incredible amount of time, energy, and money on them. Anyone have experience or advice?